Is it bad if don't use a base coat on my nails?

I usally use a top after I apply a color polish...if I add a base would it make it last longer?? Also, is it bad to wear just top coat w/o color polish?Is it bad if don't use a base coat on my nails?
I prefer if you apply a base before or your nails sometimes will turn yellowish color. and some other time even if you remove the nail polish there will still be some color on your nails. such as red nail polish or black. sometimes the blue ones left some stains.Is it bad if don't use a base coat on my nails?
the base was actually created to protect your nails from the nail polish, so try to wear a base coat one day, and see the diference for yourself.
no, none of that is bad.
Base coat is pretty much to prevent your nails from getting stained by the colors in the actual colored polish, so you might notice it lasts a little longer but it's mostly to help prevent your nails from staining. And it's actually good to wear top coat with out color it helps your nails stay strong so they don't chip or peel as easily :)