Site Up Time
One of the worst possible situations for either users or search engines is when a site is down because users nor search engines can know if the site will ever come back live again.
Situations like this have occurred even with companies like Disney where the site was down for a bit and although it probably wasn’t a huge deal for their users (because they knew Disney still existed), Google’s robots thought that Disney’s content didn’t still exist, so they actually de-indexed many pages of Disney (I don’t have a great source for this, so it could be an old wive’s tale, but I’m pretty sure I saw a legitimate source at one time, but can’t find it – sorry!).
Make sure this doesn’t happen to you!
To learn more about Site Up Time (how to properly and improperly implement, as well as how to find it on your site), signup for SEO Pro here