they don't, although if they recommend you, they'll ask you for a cut of sales (affiliate program). if you say no, they'll switch their recommendation to your competitor and never review your brand again.
I called out the inherent affiliate bias issue years ago but HN cult tunnel vision didn’t want to hear it and downvote me to hell. Wirecutter is not to be trusted.
When they link to a product on Amazon they then ask the brand to give them an additional cut of sales? I'm surprised Amazon allows sites to double dip like that.