I started my bass playing days doing Jazz at school and Billy Sheehan/Iron Maiden at home. It got to the point where I was playing faster than they were on a lot of stuff.
I got speed for sure, and I never realized that if you play with the tips of your fingers, its easier to play faster. I pluck 64 notes the same I would a whole note, since tone comes from your fingers. I also had the endurance to match it and was able to play hour long sets without a single problem or fatigue.
Back when I started bass, the faster you play the better you are, was my mindset. Its totally not the correct one in my opinion and experience. I was self taught, so I had my own exercises for speed and I played close to 8-10 hours a day on upright and bass guitar.
Now I only play bass when I'm with other people and I play guitar or piano when I got nothing else to do. My speed has greatly diminished and so has my endurance when it comes to speed playing. I get more enjoyment laying lots of big notes, which (for me) was one of the hardest things to learn.