Below is a snapshot of the franchise win-loss records (regular season) for the 30 MLB teams, as of June 6,2017. You can find the updated totals at http://www.baseball-reference.com/teams The Padres have the worst franchise record, especially when you consider that Tampa’s win % is hampered by being a fairly new team.
The Yankees are the only team a long ways above or below .500. It is surprising to see the Giants with the second best win %, but also to see that even renowned franchises, like the Cardinals, have only a .52 win %. Would you have guessed that the White Sox, Pirates, and Tigers have won more than half their games, or that the Orioles are still a long ways below .500?
Odd to see Florida/Miami in dead last, even in spite of two World Series titles. And the Cubs to be an aggregate 500 games above .500, even though they were synonymous with the word “loser” for so, so long. But nice that the NY/SF Giants are the winningest team in AL/NL/MLB history!