Causes of disadvantage in 5e?

[dco]

An orc trying to sing like the children of a chorus with high pitched voices, a person swimming with hands tied, scale a wall after an oil massage, trying to discover the secrets of the universe using a library of love novels, etc.

 

[Li Shenron]

- bringing pizza with fruit on it

You get only disadvantage for that? In Italy it's practically a crime.

 

[Toledo]

By far the largest source of disadvantage in our games is flanking. The combat positional element is HUGE in all of our games.

Four of the core players in our games are old Warhammer players (7th, 8th and earlier editions for a few), so the combat setup is ingrained in us - so we use flanking as a primary element.

We also use miniatures quite heavily (we literally have thousands from all the Warhammer playres).

We don't use a grid, but use 1"=5' and tape measures. Cool thing is that we don't premeasure. You have to guess if your character can make that 30' (6") charge to get in combat or not. This can be especially important in casting spells.