I read reviews for restaurants most often, primarily for recommended dishes and to see if service or hygiene is an issue there. I also read reviews for things I plan to use often - skincare products, home products, clothing and accessories and shoes, tech, etc. Skincare products to hear about things like "good for x skin type", texture, and smell. Home products, clothing and accessories and shoes, and tech to see if it's a good investment, ease of use, enjoyability, quality, comfort, etc., depending on what the product is.
For books, TV shows, and films, I don't usually read reviews before beginning because I like to be surprised and to form my own judgment of them. However, I do check ratings - e.g. if a movie has below a 4-5 IMDb rating (which I don't often find), then I'll briefly glance over the reviews to see if I should proceed with watching. For games, I look for spoiler-free reviews [e.g. "solid story", "amazing customization", "great QoL improvements", "best game of the year" (would then check if the reviewer has similar tastes to me, if possible), "worth it for the full price"] to decide if I should buy and play because I would still like to go in somewhat blind.