I use profiling tools more than step-debugging, and printf()/var_dump()/IO.inspect/System.out.println/&c. much more than both, because most of the time I just need to see what the data looks like in a few locations to have a solution.

Sometimes the problem doesn't show up immediately in data and the code is too complex or uses a lot of wormhole techniques like particular forms of exception abuse, that's when I might fire up the debugger and browse frames instead.