To prime or not to prime

I am guilty of not applying primer to some of my models. As a general rule, I believe applying primer is a great practice. But why? 

Applying primer to the surface of your model allows you to reveal and see any imperfections or gaps on the fuselage. You can fix those irregularities using sanding paper and then apply a second coat of primer. If necessary you can repeat the process, always being careful not to delete any important details on the model. Using primer also helps the paint to adhere better to the surface of your model.

How about you?

Do you apply a coat of primer on your model before applying the first coat of paint? 

Do you know that before applying primer, it is always a great idea to wash the parts of your model first? Washing your model will remove molding residues and allow the primer to bond better with the model parts.