Teleporting with @p on command block teleports multiple people

When a lot of people are close to a command block with a tp command with @p programmed on it and one of them activates the command block, all of the players are teleported to the destination that only one was supposed to teleport.

What happened: made a Spleef minigame on my realm and under the minigame I put command blocks with a tp command with @p on it for each player that fell would activate them by pressure plates and teleport out of the minigame. But when there were multiple people playing, the first player that fell activated the pressure plate but not just teleported him (the closest player) but all the players playing on the 30x30 platform 3 blocks up. It just doesn´t make any sense to a @p command teleport more than 1 person. The command blocks weren´t the repeat ones, they were the impulse one (the orange one).