The last time we had a raider exodus (4 heroic raiders left) I was worried about the effect on raiding but that was the end of an expansion and we didn't really need more raiders, but a few weeks later, 3 players suddenly turned up who were heroic raiders and that filled the gap.
During ToV we had a couple of raiders join who were great raiders but it turned out they probably should have been in a mythic guild (even though I am sure I strongly emphasise we are heroic only) and they left with another raider to join a mythic guild. That dropped our numbers again but we're still way over 15 so I wasn't concerned. Loss of a healer did worry me, but I have so many healers in the wings that it would be covered.
They would have only been gone for 2 weeks when I got a request from a group of 4 who wanted to join the guild who were a mixture of normal and heroic raiders. They were looking for an active guild and people to play with so I went through the whole spiel with them and they were still keen to join so I brought them along and popped them in the Sunday raid. The rogue did so well and was heroic ready so I brought him on Monday and he cruised along just fine, and since we have tons of heroic raid spots (and we have no rogue) I thought it would be fine to let him in for heroic raids. He's even already handed over a bunch of flasks for the cauldron!
And, another healer who had left to play with his friends during the twilight end of HFC (I had said to him he could come back if his friends all stopped playing) has come back after all his friends quit WoW again, and brought his brother into the guild as well. I don't know how much raiding they want to do but it does beef up the Mythic + pool.
Also joining the fray is another friend who has come back to WoW (but his guild has all gone to Barthilas, and I was encouraging him to follow them) but a few of his guildies ended up in Frostwolves. Him being here is not the concern - but having a 4th resto druid in the raiding mix is. He is heroic/mythic raiding material and I feel like it's a shame (and wasteful) not to have him raiding.
But... who knows how long this will last! There are still another 2 guildies that may leave to join a mythic raiding guild and though I'd loathe to see them go I am not keen on people feeling they need to stay out of guilt - I want people to stay because this is truly where they want to be.
But you know what's REALLY great?
This is done with no recruitment advertising! To think - I was doing so much forum browsing last expansion looking for raiders when really, now that I have settled into the no-mythic thing I don't need to have 23+ raiders - I am happy with even just 10! So we will always be able to raid, and it's just Murphy's law when you aren't looking for something, they seem to all drop in your lap.
It's either that, or we have a glowing reputation that precedes us 😁😁😁. Before my head explodes I'll just assume it's Murphy's law and see how many cycles of raider tides we go through.