Hair shampoos are a really good product to maintain healthy hair. You should not change your shampoo as long as you are getting the intended result.
However, if you feel you have achieved your result from the shampoo and want another result, maybe a shampoo for thick hair or full hair, you can change your shampoo.
Whenever you want to change your shampoo, make sure you check the component of the shampoo so you won’t damage your hair.
Do not change your shampoo every time. However, if there is an upgrade or a better version of your shampoo, you can still use that. If you are not getting your intended result, you can as well change your shampoo.