A debugger is very useful when you trace a piece of code that 1) you understand well and 2) executes relatively linearly. JavaScript is pretty terrible at both.

A debugger is very useful when you trace a piece of code that 1) you understand well and 2) executes relatively linearly. JavaScript is pretty terrible at both. First of all, most JavaScript apps are just a small chunk of code that sit on frontend frameworks (React etc). This means that using a debugger, you mostly step through framework's internal code base, of which you have a vague understanding at best. Also, an average JavaScript code hops around -- to put it mildly -- crazily, due to the heavy usage of anonymous functions, callbacks and other very cleaver abstractions. This is why placing a bunch of console.log beats tracing with a debugger.