Any computer application must respond to input within twenty-seconds or the person using it will think that the software is broken and begin pressing the "Any Key" to elicit a response.

Internet latency is not an excuse for failure to respond; c'mon, even satellite links have less than 20 second latency.
The iPhone has a 20-second rule start-up timer; if an application takes longer than 20 seconds to start up, it is killed by the iPhone OS. Also, the iPhone OS will kill any application that is unresponsive for longer than 20 seconds.

Usually seen on poorly built web pages that rely on over-taxed advertising servers.

Also violated by Windows OS during the boot process where it waits a whole freaking minute for network connections that are never connected to time out.
by BigUncleJohn October 22, 2010
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