I am not being paid to say that. I just think they provide some fantastic free services. There are too many to list here, but these are some features of their totally free services that I would like to highlight to get you to consider checking them out. There are more features that you pay for, but I am only highlighting features for free users. Go check out their website here.
The best reason to use Netlify is that you can host a private repository. Normally this is a GitHub Pro feature. That's a minimum of $84 per year that not everyone can afford.
You can set a custom subdomain (as long as it's not already being used).
If you have your own SSL certificate that you purchased, you can use your custom SSL certification instead LetsEncrypt. Otherwise they also provide an automatic LetsEncrypt SSL certificate like GitHub.
Netlify also provides the option to compress images to make for a speedier download.
When turned on, Netlify can host your site from one of their CDNs to serve to a crawler to greatly improve SEO.
You can receive up to 100 form submissions for free without having to have a backend.
You can deploy using drag & drop as well and still rollback to previous versions with a couple clicks.