Wait vs No wait in Synchronized methods (java)

Hi I'm pretty new to Java and now I'm getting into java concurrency. And I have a little doubt about Synchronized methods: i have seen that I can get the same results using an If else inside a Synchronized method, checking every time If the condition to do an action is fullfilled, as using a wait / notify approach.

Since i get the same result I'm wondering If the If else approach has any advantages or disadvantages over t'he wait and notify approach? I supose that efficiency will be a disadvantage, since If is always checking the condition, Who le wait Just stops and waits for notify. But are any other advantages or disadvantages?

Thx!