Reviewing products
There is an expectation of a glowing review. Frankly I've disappointed some by telling them that I really didn't like the product.
There is an expectation of a timely review. I put it on my "to do" list, but sometimes the review doesn't get done for a long time. That just frustrates the heck out of the product developer who thinks I've just scammed them for a free product.
Review requests sometimes have nothing to do with your field of interest. I don't like to read about knitting or snow removal. I've learned to reject those requests so I don't fall asleep at the keyboard.
Once in a while you get a surprise. A fellow Warrior asked for a review on some of his CopyWriting videos. They were simply excellent. Most products are so so, but this one blew me away.
It is for the last case that I'll not say "never again" but I pass up a bunch of them.