Fact 1: they can manipulate their tails and make it look like it's gone

fact 2:  saiyans while hiding their tails can look at the moon and stay in base form.

fact 3: tails that are not used will be weak similar to cannon

Fact 4: Saiyans Zenkai boost can be considered slow when their not damaged to near-death

Fact 5: under stress and, in an uncomfortable situation their tails get revealed. as they

Fact 6: they can adapt quick in a dangerous situation

Fact 7" the legendary super saiyan exist as something impossible for any normal saiyan nomatter if their a prince or not to get as it's an uncontrollable raging form.

Fact 8: Super Saiyan 4-6 exist.

Fact 9: saiyans are not the strongest race in the univers