I buy a product based on both my own opinion of its looks, how sturdy it looks, how well made, by company (if I like the company, I trust their quality), and I usually read most reviews before purchasing a product.
The looks get my attention, then I read the details and see if it's something I'm interested in/know I would use, and then I read the reviews to see if it's worth the price. Then I weigh the pros and cons. Hope that helped
If I'm looking at vibrating toys, I always look at the ones with the highest vibrations, set the filter to ratings, and let looks guide me. Then I read the product reviews and compare it with the other highly rated strong vibes to make my choice.
Looks are usually what attract me, but I try never to buy anything at all, especially adult goodies, without reading plenty of reviews first. I want to have a good idea of what I'm getting, especially something of such a personal nature, and when I get something online.
I have been finding that I make my more pricy purchases after looking at a lot of reviews and reading the contributors input. If the product is under $20 I do less research and just look at the ratings.