404 errors suggest that a user has landed on a page that does not exist. Most of the times it occurs due to a bad permalink, either while linking on your own site or by someone else linking to a non-existent link on your site. This may also occur when you make changes to the post slugs or permalinks on your site.
No matter what the reason is, looking at a error page is least of what a user expects when they come to your site for information.
You can always create a custom 404 page in WordPress. But that does not mean that users will be happy or you will be able to track when users come across 404 errors.
If you want to know how I handle 404 errors and fix them you might want to check a post on my tech blog to Track and fix broken links on your website.