Throw-In Mechanics

[Fritz]

Looking for some guidance; had an evaluator tell me the other night that you should always bounce the ball to the player making a throw-in. But had a senior partner tell me he hands/flips the ball if he is on the baseline and bounces it if the throw-in is along the sideline. Watched high school and college games on TV and seen both.

Just curious if anyone has a good rule of thumb to use and why. Was told that the quickest way to move up in the ranks is to make sure your mechanics are solid but haven't found anything about this.