Tire re-balance

[supradupe]

Question for the pros.

Do we need to re-balance the tires say every 2-3 year? even though there is absolutely no vibration or uneven wear/tear pattern on the tires?

In other words, if the tires were perfectly balanced when they mounted on the wheels, all we have to do is rotate them every 7k mile or so, is this right?

Thanks.
steve