I rarely check if updates are available for the majority of softwares that I have installed on my system. The reason behind this is simple. It takes a lot of time to check the websites of the developers - if they are known - and compare versions. I had to check for updates regularly which means that I would be occupied and could not do more important tasks. My estimation would be that it would take roughly between 6 and 10 hours a month to keep all of my software up to date.
