Everyone wants to yak, but few people tweet anything worth reading. This is why I try to keep my tweets per day down to a minimum- even I usually almost don't care about what I'm about to say. And the people who don't tweet very often? They are most likely too busy living life.
For every captivating tweet, I will ponder it for 5 minutes, max. There's a live feed competing for my already too-short attention span. I get on Twitter for quick friend life updates, and the occasional newsworthy link. That's it. Life prefers to carry on without distraction. At least for me, this sort of distraction is the "enemy of purposeful action."