* I sometimes have to use an empty dependency array inside useEffect to run something only when component first loads. The linter yells at me, but it makes sense. I once read an article which told to put things in functions and wrap those functions in useCallback then that'd be proper, but can't imagine the value. I think most of the internet simply does empty dependency and ignores what creators of hooks suggest.
* I want to run things before the component mounts, like API calls.
* I often want my useEffect to trigger when only one of the state variables it references is updated. Again, linter screams at me and I add an exception.
* Because useEffect triggers after component mounts, and only then, it's sometimes difficult to avoid some flicker. For example I want to do something when a components prop (say "loading") changes from "true" to "false". Loading has finished, prop has been updated, component re-rendered, and only then I can trigger what I really wanted to do on that transition. I think "componentWillReceiveProps" would have solved this, but there is no functional equivalent.
Basically if there is a person who uses "useCallback" out there "correctly" I have not met them yet. My junior subordinates misuse useEffect quiet often. I often see (and use) empty dependency arrays. I see (and use) partial dependency arrays, often adding linter exceptions. Reading articles about "proper" ways of doing it sorta makes sense but it is easy to forget what the hooks authors really meant.
I think hooks is a good feature, but the authors made too many assumptions when developing them. There is a philosophy underlying them but that philosophy is somewhat incongruent with the philosophy of "I just want to get this done". React is just one tool, I have 20 more things to do every day and understanding the full philosophy of functional dependencies and when and how to properly use "useCallback" - I just do not have time, and junior devs get confused even more.