I've been experiencing speed issues with a web service I use daily in order to perform my work today. It made me experience acutely that speed is but the key factor of a smooth user experience. Whether the fault comes from the application or not, I've experienced the phenomenon described in this article on the Grat Firewall of China by Aza Raskin:
Whereas annoyance is a good thing in the specific procrastination case described by Aza, in my case it's quite the opposite given I was trying to accomplish actual work. For the period when the speed issue took place, it made me loathe the software, regardless of where the issue came from (it could have been from my local network, I don't really know nor care).China’s great firewall carefully circumvents the want-what-you-can’t-have desire. When I last visited Beijing I tried to access the BBC expecting it to be blocked. Instead, the site came through slowly and erratically. If I waited long enough, refreshed often enough, the page just might come through. Because of the sporadic experience, I found my frustration was directed at the BBC and not at the firewall. Even with a conscious knowledge of what was going on, I had a visceral reaction that it was the BBC’s fault and not a country-wide censor.
Lesson learned: one really has to put speed and performance at the key of their software development effort. Great features are always trumped by speed given its huge impact of the joy of using a piece of software.