Modals have tentative meaning. What does it mean?
Talking about the Modals, tentative (adj.) = provisional or experimental
Tentativeness is the quality of being said provisionally or experimentally, one of the meanings conveyed by Modals.
e.g. I might be able to help.
MIGHT is considerably more tentative* than MAY. Compare the examples below:
May I use your computer?
If I’ve finished my homework and I’m really quiet, might I go out ?
Talking about people
*depending on the context, tentative can mean: uncertain, hesitant, cautious, fearful, timid, doubtful, unsure, undecided, unconvinced; considerate; attempting… :) :)