Singling out WPA here is not fair, although WPA is deserving of some of the blame. The truth is that slow play is being tolerated all across our sport, in international, national, regional, and independent events, sanctioned and unsanctioned.
We're used to glacially slow play in one pocket and straight pool matches take longer and longer than they used to, but nine ball is threatening to become nearly as slow as these other disciplines.
Nine ball hasn't changed much in the last twenty five years, so why does this generation of players need so much more time to preside over their decisions at nine ball than the last generation? Are today's players just dumber than those of twenty five year ago? Personally, I don't think so. They're only playing at snail's pace because those who oversee our sport are tolerating it.
At every level of pool, we need to stop being so tolerant of slow play. It's making the game less watchable, and thereby, less marketable.
PS I'll single out the Joss Tour and Matchroom Sports as the only pool organizations I know of that manage to consistently adhere to posted match schedules. Both make sure that their events keep moving along swiftly, understanding that it serves the interests of both players and spectators.