IMHO two major reasons:
- lack of focus
- lack of planned educational program over 2 or more years
On point one, how many koi clubs are really that? If you the club name, local, and bylaws focus on koi...how many folks in the club have koi ponds (as opposed to ponds with koi)? It is all too easy for the very small koi keeping hobby to drown in water gardening. If a club is supposed to be a koi club, then stay on track.
Point two has a synergy with point one. If the club plans and implements a REAL education program (what are koi, why isn't a koi pond a water garden, how to do I measure and maintain the water quality, how and why to QT,,,,etc.) it retain the koi kichi and attract like minded folks.
Our club has ~200 members and someone said...we need more members. One of our few koi kichi members said....no we need more koi keepers to do more work in the club.
OK, that is my morning rant....NEXT!