When your alignment is off which means that your tires are not point in the same direction. There are four things you need to consider which are steering, suspension, safety, and durability of tires. There are several problem may cause vehicle losing their alignment which are port holes, hitting a curb, and bumping into concrete parking stalls. You can check whether it is the time to do your vehicle alignment from the records that usually stick on the right side of your car front mirror. When it reaches to the certain mileage, it is the time to do maintenance of alignment. Besides, when you feel that your steering wheel vibrate or pulling to the left or right when you are driving. It is also the time to do alignment.
The technician probably will check on three things while during tire alignment which is camber, toe, and caster. Camber will check on the inward or outward angle of tire when view from the front of vehicle. It must be equal balance with not too much inward or outward to maintain the tire to stay positive camber. Toe, is the extent to which your vehicle tires look from above. Toe-in is when your car tires angle the same way, toe-out could be both tires going outward, and both are require doing adjustment. Lastly, caster check could help balancing steering which means your steering will stay straight without going to the left or right. All tires should be stay in the centerline to keep driving safety.