D&D 5E DMG question: attunement

[HobbitFan]

I was going through the magic items of the new %E DMG and reading up on attunement and such. I get that attunement is supposed to be a method of balancing and controlling magic items.
What I don't understand is how WOTC arrived at what items do or do not require attunement.
Boot of elvenkind don't require attunment but the other types of boots do?

In the guidelines for creating magical items they list a few criteria for deciding if something should require attunment (pg 285). Alot of the actual magic items doen't appear to have been picked according to those criteria, at least not consistantly so...

What's the deal?

 

[Dragongrief]

I think they went a little too simplistic explaining their first "thing to watch for." What I would consider when looking at attunement is:

1) Does it have a stack-able bonus/ability?
Gloves that add 20 feet to your range with thrown weapons are great. Gloves that add +2 damage with thrown weapons are potentially abusable.

2) Is it easily transferable between characters?
Cloaks, hats, and rings all fit into that category.

2a) Would the swapping out cause an issue?
Boots of Elvenkind, for example, would require at least a few rounds to switch between characters. It would also leave the first wearer without magical stealth assistance in an area they needed it to get to.

Hope that helps some.