Li Shenron
Legend
You can start at what
Mmm... there's kind of multiple layers with adventure design. Some random musings of mine here...
One thing about the starting level is that it sets the audience. When I want to start a new adventure, I always look at the stated starting level to decide what to pick, and I guess this is what most DMs do. If we are currently at 5th level, I'd be looking for 5th level adventures. WotC knows the statistics and have already said before that there are a lot more gaming groups playing at low levels. But what do you know when you cannot find an adventure that matches your group's current level? If you don't want to create your own, and you have to pick an adventure which is either lower or higher, what do DMs do? Do they pick the lower level adventure and "buff it up" with more or bigger monsters, or do they pick the higher level adventure and "tone it down" (or buff the PCs)? To each his own, but my bet is that it's easier (and more fun!) to increase the difficulty than decrease it, so I would look for 4th level adventures, then 3rd, then 2nd... As a matter of fact, you don't even have to necessarily increase the difficulty, D&D has a self-balancing mechanism in the fact that if the adventure is too easy, the PCs can push forward faster by taking less rest and more encounters (unless the DM forces a specific adventure calendar). WotC probably decided that, in lieu of the majority of gaming groups probably playing in tier 1, it's better to stretch the adventure start down to 1st level to capture maximum audience, than to start at 5th and have many groups not even looking at the adventure.
Another matter is how long the adventure is. In previous editions we had shorter adventures, there were a lot of published adventures which accounted for a single level-up before the end, although maybe 3-4 level-ups was considered also a standard. But I also remember that at some point people starting to want whole campaign paths or story arcs, probably because writing short homebrew adventures is easy enough but for longer ones you might want to rely on professionals to do it for you. Maybe this is the reason why WotC decided to publish almost exclusively the latter kind for 5e (I think Tales from the Spiral Staircase is the only exception, or maybe there is more?) but it doesn't have to stay the same forever.
Next thing to consider, is the separation of narrative and difficulty. It's a fact that character level matters mostly for 2 things: combat encounters, and bypassing challenges (e.g. high-level PCs having capabilities for teleporting, scrying, flying etc. that lower-level PCs don't). The two things can be separated, so you can have "save the world" scenarios at level 1, as well as "clear the rats" scenarios at level 20 (yeah that sounds quite a stretch... but I take a note to myself: try one day to come up with a "infinite rats" challenge and see if 20th levels character really find a way to solve it, since it won't be anymore a matter of simply killing them all!).
Someone else has also mentioned the very important fact that adventures are not only about battles... There are a lot of other things to do, from exploration to investigation to social encounters to crime-solving, and these actually work better when the PCs don't yet have bypass spells and abilities. But they are harder to design, and many groups just want to do battles anyway. I think no designer would risk not having at least some combat in every adventure.
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One thing that is a pet peeve of mine, is that level should probably match more with the players' skills than with the character story. I know this is hard to swallow, but the traditional idea that level represents a character's own development has drawbacks. We all know how suspension of disbelief is shaken when you have characters going from 1st to 20th in a year, then have nothing more to learn, or when you have a 20th-level teenager or viceversa you start at 1st level being an old wizard. Not to mention how many times people feel the need to introduce rules to represent training because they can't stand the PCs gaining levels while sleeping in a dungeon.
The reality is that I don't believe level was really created for narrative purposes... I think it was created to take the players forward with the game. If you can manage to see that level is for the players rather than the characters, you worry less about how the narrative matches the level. That for me also means that a published adventure starting at 1st level guarantees that the players aren't rushing towards a character complexity they cannot currently handle, and they can learn gradually how to use a new PC's abilities.
Then of course if your players are really experienced and have already played a lot of PCs, and don't need another refresher on combat superiority maneuvers or spells, then it's totally fine to start at higher level already.
Mmm... there's kind of multiple layers with adventure design. Some random musings of mine here...
One thing about the starting level is that it sets the audience. When I want to start a new adventure, I always look at the stated starting level to decide what to pick, and I guess this is what most DMs do. If we are currently at 5th level, I'd be looking for 5th level adventures. WotC knows the statistics and have already said before that there are a lot more gaming groups playing at low levels. But what do you know when you cannot find an adventure that matches your group's current level? If you don't want to create your own, and you have to pick an adventure which is either lower or higher, what do DMs do? Do they pick the lower level adventure and "buff it up" with more or bigger monsters, or do they pick the higher level adventure and "tone it down" (or buff the PCs)? To each his own, but my bet is that it's easier (and more fun!) to increase the difficulty than decrease it, so I would look for 4th level adventures, then 3rd, then 2nd... As a matter of fact, you don't even have to necessarily increase the difficulty, D&D has a self-balancing mechanism in the fact that if the adventure is too easy, the PCs can push forward faster by taking less rest and more encounters (unless the DM forces a specific adventure calendar). WotC probably decided that, in lieu of the majority of gaming groups probably playing in tier 1, it's better to stretch the adventure start down to 1st level to capture maximum audience, than to start at 5th and have many groups not even looking at the adventure.
Another matter is how long the adventure is. In previous editions we had shorter adventures, there were a lot of published adventures which accounted for a single level-up before the end, although maybe 3-4 level-ups was considered also a standard. But I also remember that at some point people starting to want whole campaign paths or story arcs, probably because writing short homebrew adventures is easy enough but for longer ones you might want to rely on professionals to do it for you. Maybe this is the reason why WotC decided to publish almost exclusively the latter kind for 5e (I think Tales from the Spiral Staircase is the only exception, or maybe there is more?) but it doesn't have to stay the same forever.
Next thing to consider, is the separation of narrative and difficulty. It's a fact that character level matters mostly for 2 things: combat encounters, and bypassing challenges (e.g. high-level PCs having capabilities for teleporting, scrying, flying etc. that lower-level PCs don't). The two things can be separated, so you can have "save the world" scenarios at level 1, as well as "clear the rats" scenarios at level 20 (yeah that sounds quite a stretch... but I take a note to myself: try one day to come up with a "infinite rats" challenge and see if 20th levels character really find a way to solve it, since it won't be anymore a matter of simply killing them all!).
Someone else has also mentioned the very important fact that adventures are not only about battles... There are a lot of other things to do, from exploration to investigation to social encounters to crime-solving, and these actually work better when the PCs don't yet have bypass spells and abilities. But they are harder to design, and many groups just want to do battles anyway. I think no designer would risk not having at least some combat in every adventure.
---
One thing that is a pet peeve of mine, is that level should probably match more with the players' skills than with the character story. I know this is hard to swallow, but the traditional idea that level represents a character's own development has drawbacks. We all know how suspension of disbelief is shaken when you have characters going from 1st to 20th in a year, then have nothing more to learn, or when you have a 20th-level teenager or viceversa you start at 1st level being an old wizard. Not to mention how many times people feel the need to introduce rules to represent training because they can't stand the PCs gaining levels while sleeping in a dungeon.
The reality is that I don't believe level was really created for narrative purposes... I think it was created to take the players forward with the game. If you can manage to see that level is for the players rather than the characters, you worry less about how the narrative matches the level. That for me also means that a published adventure starting at 1st level guarantees that the players aren't rushing towards a character complexity they cannot currently handle, and they can learn gradually how to use a new PC's abilities.
Then of course if your players are really experienced and have already played a lot of PCs, and don't need another refresher on combat superiority maneuvers or spells, then it's totally fine to start at higher level already.
