Depends on some stuff. I've actually doen a test with two identical sets of strings treating one well (like washing my hands before playing) and the other set just playing, and the difference in life was completely scary.

Tone from fingers..a lot of it is figner strength, and there's also gentleness in the mix(or digging into the music), there's overall control over the strings you develop with skill and strength, and as soon as you're at the point where you can hear your tone you'll probably just start playing in a way that makes your gear sound better to you. Unless you're rich, then you buy new gear. :)