A couple of months ago I picked up an electric Thrift Store Chainsaw.

Actually, it was one of the B&D Alligator Loppers.
I have a couple of them. They are extremely easy to use.
I like the battery powered saws, but not the B&D batteries
They are rated for small stuff, but I'll occasionally cut up to about 6" or so with them.
They are easy to use, don't kick, reasonably "safe", as technically one is supposed to hold both handles to operate both triggers.

Anyway, this was a plug-in version. It looked unused. I had it sitting in the back of my Blazer when I went to a friend's house.

I tried pruning a tree... and NOTHING.
The motor was fine.
Chain moved.
But, the thing just refused to cut at all. Just a little scratching of the bark.

On closer inspection, the chain was installed backwards

I assume the previous owner also found that it didn't cut very well with the backwards chain, and that is how it found its way to the thrift store. So far I've never broken or thrown a chain, so I have no idea how it could have been installed that way. China? An automated chain sharpener that requires the chain to be removed?

Anyway, 10 minutes later, I got the chain installed properly, and it cut like a new saw.