I'll try to make this site better continually. In this page I described how to check the suspension, buying a used car. Defects of the suspension appreciably reduce driving safety . For example too worn ball joint may disjoint unexpectedly, causing a skid. Faulty shock absorbers or struts may causing the tires to lose contact with the pavement, which also may cause a skidding.
Suspension defects change wheel alignment angle which hasten the tires wear.
So, if you have any signs that your suspension has some defect - have your car inspected as soon as possible. If this guide too complicated for you, I also have How to check a car - simplified guide. Any of these indicate some suspension wear. At first have a look. The shock absorbers should be dry, and the shock's boots should not be torn.