Strange levels between zones?

[acynatic]

For some reason the guide only tells me to go to the next zone when I'm halfway through a level, for example at level 16 and 3 bars. Why is this?

[ZG Support 1]

The recommended spots to move to the next area are not at the beginning of a new level very often. This is done for ensuring that you are able to get thru the content without needing to grind mobs or anything like that. With the upcoming changes Blizzard is making to the leveling process with 7.3.5 this will no longer be a thing and you probably won't see any suggestions for going to the next zone except when you complete the previous zone guide or hit specific levels to advance to new expansion content.