I would nominate the Miami Marlins, besides literally buying a world series the franchise has been utter crap.
Wow, you really weren't exaggerating at all
1993 MLB NL East 6th 64 98 .395 33
1994 MLB NL East 5th 51 64 .443 23½
1995 MLB NL East 4th 67 76 .469 22½
1996 MLB NL East 3rd 80 82 .494 16
1997 MLB NL East 2nd 92 70 .568 9 Won World Series (Indians) 4–3
1998 MLB NL East 5th 54 108 .333 52
1999 MLB NL East 5th 64 98 .395 39
2000 MLB NL East 3rd 79 82 .491 15½
2001 MLB NL East 4th 76 86 .469 12
2002 MLB NL East 4th 79 83 .488 23
2003 MLB NL East 2nd 91 71 .562 10 Won World Series (Yankees) 4–2
2004 MLB NL East 3rd 83 79 .512 13
2005 MLB NL East 3rd 83 79 .512 7
2006 MLB NL East 4th 78 84 .481 19
2007 MLB NL East 5th 71 91 .438 18
2008 MLB NL East 3rd 84 77 .522 7½
2009 MLB NL East 2nd 87 75 .537 6
2010 MLB NL East 3rd 80 82 .494 17
2011 MLB NL East 5th 72 90 .444 30
2012 MLB NL East 5th 69 93 .426 29
2013 MLB NL East 5th 62 100 .383 34
2014 MLB NL East 4th 77 85 .475 19
2015 MLB NL East 3rd 71 91 .438 19
2016 MLB NL East 3rd 79 82 .491 15½
2017 MLB NL East 2nd 77 85 .475 20
2018 MLB NL East 5th 63 98 .391 26½