In D&D 5.0 and 5.5, what is/are the WORST multiclass combinations that you can think of?

Hi all, a little bit of a thought exercise I was wondering for myself; what is/are the WORST multi-class character(s) that you can come up with?

You can go up to whatever level you like, and MC as many time as you like while staying within the rules for Multi classing.

The one I though about it for a while and the Best... err... worst one I can think of is Oath Of Glory Paladin/Four Elements monk.

What are your top... err... bottom picks?