That was an excellent reply. *jealous*I thought the basis of everything you've been saying is you're the BEST at killing things?!
See that's what I didn't get.
I getcha now, in terms of inviting someone to my group (more often my guild since I rarely run PUG groups) there's always a few key factors.
1) Do they know their class?
This is determined by asking a player I trust to know their class to conduct a mini-Q&A to see if this person can talk the talk.
2) Are they available at the time we raid/play?
Pretty easy to figure out, but people have to be honest about this one, because if you can't show up, obviously you're not going to contribute much.
3) Can I tolerate listening to them/Can they tolerate listening to me?
This is tougher to establish, and usually why we have a probation period.
If people decide that the guild isn't to their liking or we decide it's a personality clash, call it quits no hard feelings.
This has very rarely been the issue as any guild I've been involved in was very upfront about our personality.
Gear is actually fairly low on my concern list, as there's usually old content you can fly through to rapidly gear new recruits.
Most good guilds can run a raid successfully even with a handicap.
If you just meant how do I decide if (I'm assuming you're basing this on WoW, since there's the GS discussion) I want to invite someone to a 5 or 10 man raid, the answer is all about personality.
When I form a PuG I always bring a tank and a healer I trust, or fill those roles myself.
As long as I have that covered, I can pretty much fill up the rest of the run with anyone.
I really have not found WoW content hard enough my mates can't cover while we educate some PuG players and make things smooth.