As more experienced users know, votes work differently on Meta. However, the tooltips still say the same as on other StackExchange sites:
The tooltips are:
- Question up vote: This question shows research effort; it is useful and clear.
- Question down vote: This question does not show any research effort; it is unclear or not useful.
- Answer up vote: This answer is useful.
- Answer down vote: This answer is not useful.
I think the tooltips should be fixed on meta to speak their actual meaning.
Although I understand why the votes have different meaning on Meta, it is quite a bad practice to change the expected behaviour of already established elements. In this situation maximum should be done to correct for this bad practice; either by some notifications to the new user, pop-ups, ... Fixing wrong tooltips is the absolute minimum that should surely be done in this regard.