Why does the NFL's 3rd-string QB rule exist?

The rule was created to allow for teams to enable teams to have an emergency qb available who was not on the 45 man roster. Most teams only carry/carried 2 qbs on their roster to use another guy for special teams as oppossed to a 3rd string player who almost definately would not play.

The fact that you can't reenter the 1st or 2nd string qb if the 3rd qb was implemented to keep teams from abusing the rule and essentially playing with 46 players as oppossed to 45

The rule was created because most teams have only 2 active QBs and the 3rd QB spot is inactive. The rule allows an inactive player to play in essence, something that was not allowed til the 90s. So the rule itself isn't to prevent an unfair advantage, rather create a loophole so teams can have an emergency QB without using a roster spot up.

Guy above it's the 45 man active roster the 3rd QB is not on. The regular roster is 53 and 8 are inactive each Sunday

Only if the 3rd string quarterback is put into the game before the 4th quarter and the 1st or 2nd string QB's are not allowed back into the game. That rule actually was talked about a lot in Chicago following the Bears Packers NFC championship game. Haine (the 3rd string quarterback) was put in at the end of the 3rd quarter to replace the pathetic Todd Collins. Since he was put in it made Cutler and Collins inactive for the remainder of the game. It is a rule they have because the 3rd string QB is not on the 45 man active roster, so if a team decides to use him they can no longer use the 1st or 2nd string QB's.

The funny thing is the Bears put Haine in at the end of the 3rd quarter and only ran 2 running plays that quarter. Do you really need to change QB's to run the ball?

Bad A*s yeah I did spell Haine's name wrong I was in a hurry, but check your facts both QB's are made inactive. I put a link for ya to read.

The rule states that if you put the 3rd string QB in to the game your starter and 2nd string QB can't return to the game, unless it is in the last quarter, My answer to why this rule exists would be that the 3rd QB's roster spot was not supposed to be a roster spot, but because a team then could get 2 QB's injured in one game and they wouldn't be able to field a QB they added a 3rd QB spot, which is only intended to be used in case that both the QB's get injured.

It was put into place after the "Body-Bag Game"

Because......it does, theres really no good reason for it

Bad ***- He ment Caleb Hainey or however you spell it