Why don't teams with weak 4th and 5th starters put their ace on a 4 day rotation ?

Question

Innings pitched by starters are so low compared to thr 50's 60's and 70's and these guys are supposedly in better shape.

Who cares if it shortens their careers, they will become a free agent anyway.

Answer 1

They would be worn out by august if teams did that.  How would you feel if your best pitcher on your favorite team shut it down in august in a pennant race.

Answer 2

Because they want to keep them as long as possible and get the best possible results from them for EACH start

Answer 3

Well... the plan, most of the time, is to keep a pitcher long term. Even if it does not happen. But, it is VERY unhealthy on a pitchers arm to pitch on that short of rest. Especially in a 160 game season. That would also shorten pitch count during a game and get into the bullpen more often and as we have season this year by many teams, that would hurt a lot of teams.  

Answer 4

Because steroids take 5 days to kick in everytime.  

Answer 5

You want to keep you top pitchers in the best shape you can.  Too many inings mean they won't be in the best shape they can come the end of the year for a playoff run.  Back in the 50's, 60's and 70's the season wasn't quite as long as it is today.  By pitching a 4th and 5th starter you give your better pitchers a better chance of going out and getting a win each time they take the mound.  It's all about keeping your pitcher around for the WHOLE season.

Answer 6

because pitchers arms get tired after throwing 100 pitches. they need the 5 day rest. the old days were lame. a average fastball in the 50s was probably 70 mph lol.

Answer 7

Because they dont want their ace to get injured and start breaking down.

Answer 8

Number 1: The reason why players dont go as long is because of how good hitters are these days.  Back then, hitters wernt as good so pitchers didnt have to throw as many pitches.

Number 2: It would be incredibly selfish to ruin a guys career by overusing them everyday.

Number 3: If starters these days started throwin evry 4th day, they would be less effective and if they start losing there Ace productiveness it would kinda ruin the whole point.