That someone better
I want players to solve puzzles and problems and express themselves through gameplay choices against puzzles and situations. It's fine and good if a player finds a way to fix an issue in 3 die rolls, but it's horrible to design an issue that's solved (or is meant to be solved) by 3 die rolls.
You are correct. This is an example of Bad design.
I went into more detail in my last post, but I hardly think those are the only options, there's lots of possible resource expenditure structures, and it's certainly possible to play the game with consistently repeatable techniques. After all, it's not like anyone seriously expects to drain all of a caster's slots on Spider Climb. The difference between being able to do it once when it's relevant and all the time is quite slim.
I agree. My reply was specifically directed at bringing skills in-line with the OP's expectations vs. D&D's magic system...
Outside of that:
These questions about skills being seen as random vs combat or magic is a discussion that only D&D players seems to have. I think that it is largely a matter of conflicting expectations due to the way D&D scales combat, magic, and HP, vs. its skill progression.
You should not roll unless the PC is having to perform under stress of some kind, and failure is meaningful.
Skill based RPGs make this very clear.
These kind of discussions about "huge margin of failures" for PC's in "everyday tasks" never really come up because they are are non issues. This is due to Skill based RPG's being designed around their skill system. It is not something tacked on to a class based ability system like with WotC D&D.
In my opinion; the PHB and DMG set D&D GM's up for failure here:
Yes, roll if the outcome is uncertain, but the base DC 10 is called "easy"... GM's are being sent contradictory messages on how to set task difficulty, and when to roll.
DC 10 should be - Standard acting under stress (SNAFU) roll. The basic roll when a PC has to perform on demand, yet there are factors that can cause them to fail. Your training should be enough for you to do it, but there are factors that can cause you to screw up.
DC 15 - Difficult - Acting under stress and there are other factors that makes the task harder. Only trained professionals can reliably pull this off...
DC 20 - Hard - The situation or obstacle is exceptionally difficult. Only a trained pro has a chance at success... Or you need to get lucky.
DC 25 - Only with great difficulty. A coin flip for even the most well trained adventurers.
DC 30 - May your gods be with you...
Etc.... This is all just off of the top of my head - in reality more thought needs to be put into this kind of delineation.
WotC D&D has had skill systems that have always had a tacked-on feel to their class/level based game, and they do a bad job of explaining how such skill systems should work in actual play.
In my opinion; I don't think having an explicit 'skill list' is a good idea for class-ability based games.
Something more like Backgrounds/Careers as "skills" - as done in Barbarians of Lemuria RPG is a much better fit for the type of gameplay that D&D generally encourages.