Xojo is not an acronym.
@Sam R Oh oh I got one - Apple's yearly OS updates :)
Apple's yearly OS experiments :P
I used to be one of those "install first ask questions later" people
As OS X rolled along and updates became yearly they also seemed to decline in overall quality & reliability so after about 10.6 I do not do the update on my working machine. Only ever a secondary bootable drive.
Once they get to about a point 2 or 3 release I might update.
10.10 and 10.11 seem to have proven the efficacy of this approach IMHO