Why is it that when democrat takes office he has to clean a mess left by republicans?

from 68 to 76 We had Nixon and Ford, they did a good job at ruining the country. 77-81 we had Carter (only democrat that was useless) 81-92 reagan and Bush Sr who did an outstanding job screwing the country over with several recessions, including a big one during the first couple of yours under Reagan, very high deficit, Clinton took office from 93-2000 and cleaned up gigantic mess, Bush Jr occupied the office from 2001- 2009 (still in office) does perfect job of ruining the country. Obama has to clean up Bush's mess. Why is that?? Personally I believe if you make a mess you should clean it up and not leave it for someone else.