This is a skill science fiction and fantasy writers are keenly aware of, because they often have a great deal of information to convey that the reader has no way of knowing unless told…If the information is poured out as a lecture, barely concealed by some stupid device — “Oh, Captain, do tell me how the anti-matter dissimulator works!”…we have what science fiction writers call an Expository Lump. Crafty writers (in any genre) don’t allow Exposition to form Lumps…They break up the information, grind it fine, and make it into bricks to build the story with…invisible exposition.Steering the Craft – Ursula Le Guin
Character backstories are “expository lumps.”
Instead of letting us find out who the character is by deeds and words during play, they tell us who the character is before we start.
I would rather be surprised by a small, discrete piece of information that hints at deeper mysteries of the character.
The party is passing through a nameless hamlet. They are on their way to an ancient forest where ruins of an elf city are rumored.
Tristan, the first level fighter to the DM: Do I see any cottages with milk cows?
DM: Yes, there are a couple cottages with cows.
Tristan: I approach one of the cottages and ask the peasants living there if they have any cheese they could sell.
DM: Cheese? Uh, Sure. Yes, one of the peasants says they have a little extra they could part with for five copper pieces.
Tristan: I pull out five silver pieces and say “Keep the change.” I cut a bite size piece of cheese, look at it for a moment and put it in my mouth. I wipe away a tear and put the rest of the cheese in my pack. I nod to the peasant and rejoin the party.