The previous poster was talking about Krita (and the one before that Krita and Gimp) and while I agree with some of the criticism of gimps UI, I stand by my comment a lot of that criticism is based around "it is not like program X, that I'm used to".

I mentioned it in a different post, blender is the prime exhibit for this, its UI received even more criticism than gimps. Now that it has become the (or one of the) most popular 3d modelling tool, most of these voices disappeared, because it has become the first entry point and people are not used to some other way of working anymore.