In the major tournaments, each player gets 3 'challenges' per set to see whether a ball was in or not. Every other point is judged by human line judges, but Hawkeye already knows on EVERY point whether the ball was in or not. So whats the point of line judges? You still need an umpire for the overall game but if a computer accurately knows whether each point is in or not, lose the line judges and remove mistakes!
I concur. If the ATP and WTA are going to consider Hawkeye valid for challenges, then they should consider it valid for all points. They should just link Hawkeye to the umpire's computer and have him call shots out when Hawkeye alerts him. Plus, I don't like the idea of throwing unnecessary strategy into the game for the players using challenges. They have enough to worry about... it's the ATP/WTA's job to officiate matches, not the players'. I think it's time for the ATP/WTA and the players to decide that they trust the technology enough to eliminate human error. No more line judges!
Firstly, not all the court have the system, mostly just the main courts. Why because it is expensive. Also it is probably not extremely quick. So lets say it is out, the people playing might hit the ball a couple of more time before the call is made.