If the load is caused by people actually wanting to buy a item from you like a Phone, or people wanting to use your product like Netflix, gMail etc, then downti

If the load is caused by people actually wanting to buy a item from you like a Phone, or people wanting to use your product like Netflix, gMail etc, then downtime is a serious problem as your losing sales and/or damaging the product. Even more so if it was a date and time publicly stated by the company, they should've put even more testing and preparation into it. However if it's something like a side company blog which has got popular then it's not 'critical' to have it up all of the time, but they should certainly try to as it doesn't help the company image.