There are several link building practices that can be harmful to your site’s SEO and can even result in penalties from Google. First, buying links is a big no-no. While this may seem like an easy shortcut to acquire backlinks, it’s against Google’s guidelines and can result in a penalty.
Another practice to avoid is participating in link farms, where websites exchange links solely for SEO purposes without providing any real value. These types of links are often low-quality and can negatively impact your site’s authority.
Additionally, over-optimizing anchor text is risky. If you repeatedly use the same exact match keywords as anchor text, it can raise a red flag to search engines that you're manipulating rankings. It's best to use a variety of anchor text to keep it natural.
Finally, spammy blog comments or auto-generated links should be avoided as they provide little value and could harm your site’s reputation. Always focus on ethical, white-hat link building strategies that emphasize quality over quantity. For more on what to avoid, check out https://linkbuilder.com/blog/what-is-link-building-for-seo.