> 5. It has enough storage left for your app.

This is the wildest part. It seems that sub-250MB apps are the rarity now. So every 4 apps I install is 1GB. I guess it's good for Apple, since they know you can't back up to your SSD so will then have to buy iCloud (unless you're savvy enough to open up Terminal and make a symbolic link to an external drive – the fact that they don't enable manual changing of the backup location is unjustifiable).