As long as the tub is still structurally sound (i.e,, the hole is not a puncture but a cosmetic ding), I like this easy fix.There are a couple of brands.Here is one I have used that is widely available: https://www.amazon.com/dp/B000RNPGKO/ref=twister_B006ZHK5IE?

We were putting a nail in the wall in the hallway to hang a picture last night and it looks like the nail punctured through the tile.

Roof repairs, caused by fallen trees, Cable Dishes on homes, natural disasters from heavy winds, can puncture that theory to pieces.

I've had a tree fall on a rental and puncture the roof no one was hurt, but the roof and some of the structure had to be repaired.

I'm thinking that it would add a considerable safety margin, strengthen the hull from impacts being flexible and from any minor puncture, the material may be a line of second defense holding water out.

We had a large tree fall on a rental that punctured the roof and damaged some of the structure fortunately no one inside was hurt.

Something from outside punctured it?  

Did one of you put a nail in a wall to hang a picture and slightly puncture a water line?

It could be someone put a nail in a wall and punctured a line.

It's recommended they puncture the deck by quarter inch or so.