You can not polish out a scratch, no matter how long you try.
The wire you use to burn a line in a duck call will also burn a line in your fingers, much faster.
Catches and blowouts always happen when you are almost done with the turning.
You will wish you had a drawbar on your Jacobs chuck if it ever comes out of the tailstock while the bit is still in the wood !
You can not put a draw bar on a Jacobs chuck while it is in the tailstock, and still use the mechanical advance.
You can not wipe off the Gorilla Glue on your fingers quick enough to avoid a stain in the same place on your finger later.
If you dip your calls, you WILL have a drip edge somewhere, it can not be avoided.
Zebra Wood smells like cow pizz when you turn it (I swear this is true, sorry)
You can not tune a tone board if it came out of a bad jig.
If you don't know how to tune a tone board, you will never figure out it's the jig!
Someone, somewhere, on some forum, has been there, done that, and is willing to help.