I think the easiest explanation is that GC Headquarters didn't like the direction competitive caching was going. A team of cachers would go out and achieve some goal and create a Challenge. Another team would go out, beat that goal, and create a harder Challenge. All this extreme team caching created Challenges that the average group of cachers could not achieve, much less a single cacher.
The Challenge to find 1,000 caches in a day is the obvious lie. Put a group together with one driver, two or three runners, and a log signer and bump the containers down the line, it can be done. And everyone in the group claims a find, even though the driver and the log signer found none, and the runners each found only 1/2 or 1/3 of the containers. But no one person could go out, park, get the cache, sign the log, put the cache back, return to the vehicle, and drive 1/10 mile to the next one at the rate of 1 minute and 26.4 seconds per cache for a period of 24 hours.