Disagree
The rovers need to overwinter on a sun-facing slope. As mobility degrades (with more wheel problems) the mission controllers will become more cautious and park-up earlier in the winter season and set off later in spring, but I think they'll keep trying to rove until the damn things are near dead - and we're talking many years here.
of course, if the shuttle black hole keeps swallowing science money, then thay'll shut evberything down, working or not...