Cleaning the winter cover... why?

[Spensar]

I don't clean it. I lay it out to dry and fold 'er up. We don't have a good spot, with the best on the driveway plus garden plus lawn, so it would be clean one side, flip and the other is full of dirt from the ground anyway - so, no wash. I'm in a solid winter area so I open and close to clear water and the cover is frozen solid most of the time. I put it on as late in the year as possible to, so it is pretty clean. There are plenty of maple tree seeds, leafs and other vegetation to clean up anyway, and the bit of extra dirt from the cover is marginal.