My problem with GIMP is that there's too many ways to access controls and some controls only appear in certain menus. You've got the iconographic tool picker which has submenus on right-click for some tools. Then there's the classic menu ribbon at the top which has most things you expect. Then there's the right-click context menu inside the canvas that has a subset of all other menu items. And then you have inscrutable hotkeys. Some actions are reasonable, others are not. There's too many hotkey layers with modifier keys and some actions which should be on the same layer are not.

Then there's the escape key. Sometimes it does what you want, other times it just gives you an error ding with no other information.

The core problem with GIMP is that the interface is bad. No two ways about it, it's just bad. It needs a total redesign, but that would be unacceptable as it would alienate evryobe who has already learned it.

As an editing program, GIMP does everything you need and then some. It's fully featured and functional, just not usable.

That said, GIMP is still my only choice for photo editing. All the other options are worse in different and mostly worse ways.