There are 2 kinds of mods: incremental mods and radical mods.

Most incremental mods get finished because the time to completion is less than the span of motivation. The problem is that these run-off the mill mods aren't different enough for most talented mappers to be interested.

Then there are radical mods. Now mappers become interested. One of the mods Reno talks about is paroxysm. We had some of the most talented mappers i know working on it including CJ and CJ. Yet it died.

The problem is that these mods need an incredible and lasting amount of motivation from the key members in the dev team, and a big fanbase community. Fortress Forever is one of such mods who has this. But here there's a history, and in that respect it isnt radical gameplay-wise (rather implemetation-wise).

i only commit myself to mods where i know i will have enough motivation to complete atleast one map, and where i know the mod has the 2 elements mentioned above. But for truly radical mods you can never be certain that these 2 elements will remain as time goes by, as was the case for paroxysm.