I think, if we do a poll today, we will find out that most people’s Mac systems are slower than they used to be when they initially bought it. Most of us don’t like deleting unnecessary stuff and junk often which causes our system to slow down gradually. Simply put, the cleaner your system will be, the more efficiently you’ll be able to utilize it.
I get it. It can be quite tedious task to look scrounge every file and folder and look for unnecessary and outdated stuff to delete. That’s why some business owners prefer to hire someone for this very job.
But if you are a small business owner or simply using it for your own personal use, you can use Disk Diag to help clean up most of the junk and unnecessary files that you don’t need anymore. The lack of information about what it’s suggesting deleting might be quite uneasy for some people, but rest assured, it knows what needs to be deleted!
Source - Disk Diag