tight spot in chain

[DAD]

Tight spots are portions of the chain that stretch at different rates and cause binding between links. So, why not just run the chain really loose? Well, too loose and the chain runs the risk of flying off the sprockets. Bad news! Could take part of your leg with it. Chains get tight spots from being adjusted to tight but in all my time riding I have never come across a chain without a tight spot?
I think the chain just stretches more in some spots than others.
So rotate the wheel and push up on chain until you find the tight spot and adjust at this point.