I mean, geez...his first two seasons he came off the bench as a skinny kid, then he only played half a year (the 98-99 lockout). Since then, he's averaged roughly 28 points per game in 12 regular seasons and won five NBA championships. He's also been paired with Shaq for much of his career, which meant sharing the ball more than he wanted to throughout his first eight years in the league.

Which leads to the volume thing...yeah. Kobe likes to shoot. Still, some would have you believe he's on an Iverson level of inefficiency when that's pretty damn far from the truth. He's a guy who believes he can get the job done better than anybody else - and while that's true in many cases, it's also led to him taking WAY more shots than he should have taken.
That helps to explain his conversion rate in the clutch, where he's demonstrated that he CAN make the impossible, game-determining shots but also tries to do it too often. It's been to his own detriment, because any casual observer can clearly see that he is an extremely effective option with the game on the line.