It depends, I'm rough on sunglasses and they tend to scratch a lot. I've had them fall out of pockets, etc. Also when running I've had a real issue with sweat in the summer behind them so I would stuff them into my pocket.

So I buy middle of the line sunglasses and just cycle through them. My favorites are a no-name pair from that online store that starts with a A that are clear and darken in the sun. These are great when doing an early morning ride/run where the sun really isn't up and bright but is by the end of the run. -- https://smile.amazon.com/ROCKBROS-Sunglasses-Photochromic-Running-Protection/dp/B083JS5ZMF

The price is such that I don't cry when I have to swap them out.