Comment by al_borland

#1 is especially annoying when it locks up your ability to type, because the site is busy trying to query the first 2-3 letters of the input. The whole process ends up taking longer. If #1 causes #3 to suffer in any way, it's an anti-feature and slows everything down.

#2 can be an issue the opposite way as well, such as manufactured delays. Think of a modal window that pops-up after you've been on a site for 5 seconds and are just about to click a link, but instead click the modal. Or you begin reading, are 2 sentences in, and the modal pops up. When this happens, I close the page. It's so frustrating.