Scrutinizing Screen Protectors

My Galaxy Note 8 is on its fourth Zagg InvisibleShield, the first three having developed cracks with no drops or blunt force applied to them. They carry lifetime warranties, so I am entitled to new ones...after I order them...and wait two weeks...and then visit the nearest Verizon store because I don't dare try to attach them myself.

And now the fourth one has developed a crack.

I can't imagine that whatever caused these Zaggs to crack would have caused damage to an unprotected screen so this is starting to beg the question for me: Are screen shields worth it?

I paid many hundreds of dollars for my Note 8 and I don't mind investing a bit more to protect its screen, but this is getting a bit ridiculous. What do others think? How many of you go commando with your screens? Are there others getting frustrated with the Zagg shields? Are there other products I should use instead? Or maybe I really can go without anything on these class screens that are said to be indestructible.

All comments welcome...