I use Photoshop. I'm good because I practice starting from the most basic stuff. Lines, curves, edges, form..

Imo the brushes, tools and programs used don't matter. Without enough practice on fundamentals the work will still look like shit.

One of my peeves with most 'self-taught artists' is that they tend to ignore these fundamentals because they want to skip to the cool parts. They want to develop their so-called 'art style' so badly. Tbh it's also the case with most artists here on dA.