Why does it matter who was put on the block on Big Brother tonight?

I don't understand why Michelle and Kevin are so upset about being put on the block. If Michelle or Kevin win the veto, they will take themselves off the block and Jordan will be put up. If Jordan wins, she will leave things the same. Natalie can't play in the veto competition, so the only person who is safe (besides her) is the winner of the veto competition. Right?