How big of a volatility would be worth it for straddles?

Been trying to learn how to use a long straddle, but I am not sure on how volatile must the underlying be for long straddles to be profitable

 

If you are buying options volatility should be low.

 

The price movement on the underlying must be larger than the premium that you paid to buy the straddle.

 

Most people don't dynamically hedge so ...

 

Thanks so much man