I set the slider bars to maximum for engine, and minimum for gameplay and story/quest.
The game in question is a Horror/Adventure. Something looked wrong, so I took a screenshot, and then zoomed in. That would be when I noticed this:
Followup: set everything to minimum. This should make all bars equal. They still are not. Story/quest blue has a small amount more. than the other sections permanently.
I have noticed too that the 10% on the right is much longer on the graph than the 10% on the left.
Example take stage 1, any genre, put Engine and Gameplay to the top, and Story/quests to the minimum on the sliders, and measure Story/quests on the graph underneath.
Repeat with Engine to the minimum, and maximum to Gameplay and Story/quests.
10% Engine will always be shorter than 10% Story/quests.
I must admit, it would help a BIG LOT if the actual percentages were written on the graph below, because it is visually unaccurate.
I admit i have noticed this also, i usually fiddle with the bars till i make them more equal. I have created a bug report for the devs to look at. When i get feedback I will let you know.