I like a lot of emf's work, but I do find information on his mods a bit hard to find. In this particular case, what exactly does all this new information mean? Emf does actually explain in bits and pieces, but it's hard to find ... so, let me help out:

Q: What does this mod do?
A: Shows you the requirements, and how close you are to reaching those requirements, to level up a building. For example, you need a certain about of Service, Happiness, and Education to level up a building. Once all three bars fill* the building should level up.

Q: So what do all the little bars show?
A: This is a breakdown of the "Services" bar. Basically ... how do you fill up the Services bar? By filling those individual bars. Note that you do NOT need to fill each individual bar to max. What this shows you is how much "wiggle room" you have for each service. For example, if you're only half-filled the Service bar, you can look at the little bars and see which ones are the smallest. These services should be your target for raising. Once a service's bar fills, then any more service spam won't work - you've hit the cap.

Q: What are the little bars different lengths?
A: "The bars ... sizes reflect how big a factor each service is." "the bars are proportional to how big a factor that service is to the building. So basically fire coverage is very important to Industrial."

Q: On hover, what do the numbers mean?
A: For services, their maximum "score." I'm not sure how the score is calculated exactly - I assume when a service vehicle drives past it goes up (and deteriorates with time?) For the big bars, you see the min/current/max scores. If current drops below min, the building will be abandoned, and if it hits max it, well, will max out. Once all requirements max out, the building upgrades. Note that these numbers tend to be out of 500, but the bar fills to halfway with the first 100 points.

Q: What's the relationship with this mod and "Proper Hardness" mod.
A: Emf's proper hardness came first, and he had this handy-dandy breakdown on the buildings. There was a lot of requesting that he split it out as standalone so people could use it in the vanilla game.

Q: Ugh! Building names and descriptions! I hate them!
A: Press "N"

Q: Will this mod worth with other mods?
A: The values are based off the Vanilla game values... any mod that changes these level up requirements (e.g. Level Up Balance Mod) will mean the numbers are wrong. This would even be true for Emf's Proper Hardness Mod, but it comes bundled with this feature so this mod and that mod won't work together anyway. "The little bars with all the individual factors is independant of difficulty. So just keep filling up the lowest one until the building levels. The base game already tells you if it's lacking service/land value or education if you mouse over the "original" progress bar."

Q: Can you translate the descriptions?
A: YOU can, if you want: https://github.com/lxteo/Cities-Skylines-Extended-Building-Info



* - Note: With CO's "Hardness Mod", the bars will fill up prematurely since the requirements are raised. Tooltip should still show the right requirements (I think?)