Why do billionaires do this? give money to candidates have opposite views in election?

For example Donald Trump supported Reagan in the 1980s, but donated money to carter administration when the poll is dead locked. He gave money to both kerry and bush campaign. Michael bloomberg gave money to both George H.w. bush and bill Clinton. And henry kravis gave money to michael dukakis and george h.w. bush. If someone whos completely opposite of their ideologies get elected, wouldnt that be bad for them.