Where do you get that info from?
Nowhere. It's not "info," it's a gut feeling primarily supported by the ways people
talk about the stuff their players tackle, or are exposed to, over the course of an adventuring day.
Personally I'd think 1-3 encounters per long rest was more typical.
I...have never seen
anything which suggested to me that the average group faces only 2 combats a day. If that were the case, then (at least in theory) the game would expect you to not take
any short rests at all, unless the group is trying to punch pretty damn far above its weight (and thus depleting all of its short-rest, and much of its long-rest, resources with each combat).
My 5e party's most recent 'adventuring day' in the Ruins of the Gorgon involved: a trap, a non-combat encounter (feral gnomes), a fight (living statues), a fight (the Gorgon), a fight (shadows), and a non-combat encounter outside the dungeon. So three fights, and that felt like a pretty tense, eventful day. Six fights in one day seems pretty extreme to me, eight fights seems highly unlikely.
At the end of that, the party resource drain is as follows (they started the day already down some hd):
Status
Rey, Rogue 7: -0 hp -7 hd
Hakeem, Barbarian 8: -0 hp -8 hd
Bjornalf, Warlock 7: -16 hp -7 hd
So everyone is out of hit dice and the squishy warlock is also down hit points.
Yeah, as others have said: you don't have a healer, which hurts a ton. Depending on how your characters are built, you might not even have any ranged characters, which can be another serious blow. And you're at only 3 bodies on the field, which has
all sorts of difficulty-increasing effects. So...I find it at least somewhat unlikely that your experience is highly representative of "most" groups.
Further, I think it would be really weird for the designers to make a game where there are lots of short-rest dependent classes...and it's not only normal but
expected that groups have only a single encounter in a given day. There's no benefit to being short-rest-based instead of long-rest-based if, most of the time, you can expect to rarely
need more than 1 short rest in a day.
Discounting the single time that I had an all-fighter party where they took many rests (after dropping to near 0 HP) in one day, about 1-2 is the common amount. This is with me putting no meaningful clocks on the party at all (it's typically based on geographically separate areas and how brutalized they've been).
interesting,y enough 50% of those who voted take around 2 short rests per long rest.
While that's technically true, a fairly significantly greater number of people (48 vs. 41) are centered around 1 short rest per day (that is, categories 0-1, 1, and 1-2) than is centered around 2 per day (categories 1-2, 2, and 2-3).
If we do a weighted average of the current votes, less those voting for non-numerical categories (8 votes, so n=72 as of this post), treating "4+" as though it were exactly 4 and each X-Y as being X.5, we get:
(0*5+.5*14+1*9+1.5*25+2*11+2.5*5+3*0+3.5*2+4*1)/72 = 1.375
Which is fairly close to alternating one or two rests each day. Even if the 8 discounted votes were all exactly 2, the average would
still be less than 2 short rests per long--in fact, it would still be less than 1.5 rests per day (w.avg = 1.4375).
I can only lament that this poll is really not very useful for getting meaningful data; it would be incredibly nice to couple it with a "How many combats do you typically have between long rests?" That could let us make meaningful analysis of these things, to see if some general advice might be useful. Unfortunately that's basically impossible.
