Release
You run into all kinds. Your story isn't unfamiliar to most people.
I ran a weekend league for a good group of about 12-16 guys a couple seasons ago. All were nice guys, but it became a headache trying to get people to keep me informed about their availability. I had to be a dick one Saturday because one guy in the group didn't contact me by the deadline to let me know he was available, so I left him off the roster and located a replacement. Saturday rolls around and sure enough - the guy pulls in 2 minutes before our first starting time for the group and asks, "who am I playing with?"
I told him he would have to find another group who had an opening that day because we had 16 players and didn't have room. He got pissy with me about it. I just reminded him that he'd done this several times over the season already but we worked it out because we had room during those instances, even though in doing so it suddenly changed both the teams and the format at the last second. I told him we couldn't make it work this time, and also reminded him to let me know his availability before the stated Wednesday evening deadline.
He wasn't the only one who made a habit of not keeping me posted, there were a couple others.
Then occasionally you'd hear guys bellyache about having to play with so-and-so, or wanted to play with so-and-so. One weekend it got to the point where I just picked three guys, told the rest of the group to make their own teams and matches, no group thing today. Then more whining.
And honestly, these guys were good people... they never complained about winning or losing, never complained about handicaps, etc. but they just made the process unenjoyable because some of them would either not keep me posted about availability or ask why they happened to get paired up with so-and-so for two consecutive rounds.
Sometimes stuff happens. Sometimes there's no way to avoid putting two guys in the same group back-to-back days because of an honest attempt to keep the teams balanced and competitive based on handicaps.
At the end of the season we had our season-ending tournament, and I thanked them for participating. But I also told them that I no longer wanted to be part of a big group. So three guys from the league decided to join me and we formed our own weekend foursome. They're reliable, we keep each other posted about certain dates we're out of town or unavailable, and we all enjoy each other's company and enjoy fair and competitive matches.
This has been my first season not running a group, and I must say that it has been wonderful not having to deal with it.