It is a good idea to have someone spellcheck your website. A lot of times, time is short and the website is quickly updated. So, mistakes can be made. So, always check your website for spelling mistakes. If you update your website often, then it is a must.

Also, if your website has a lot of pages, it's best to use software. Why would you want to go to every page and check when you could have a report with all of the mistakes?