You solo the kick drum, add an EQ plugin, and tweak it until the kick sounds great. You move on to the snare, solo it, and do the same thing. Then you solo the vocals and compress them in isolation. And you slowly move through your mix, using the solo button to shape each track individually.
It’s tempting to work this way. After all, it’s easier to focus on one track at a time. Since you’re not being distracted by other sounds, you can hear subtle changes more clearly. And this helps you make better choices, right?