What is "better"?

Anecdote: New member posts a novice-level track. Feedback is as follows.
"Try to make your flings stronger"
"Make your manuals smoother"
"I see lots of potential for you!"
"etc. etc. etc."
New member says "My next track will be much better."

Discuss:
What makes a track "better"?
How do you gauge improvement?
When is somebody considered at their apex (can't improve much further)?

1. better flow, more "artistic" scenery, smoother manuals, mostly subjective things oddly. It's not as though we can gauge linerider by a thing as simple as a K/D ratio or speedrun.

2. "is this track more appealing than the last?/did I enjoy watching it more?" as stated previously this is a difficult thing to measure as it's almost entirely in the mind. I remember when I posted the untitled preview and people said "ohh a massive skill jump at the end" when that part was probably actually one of the easiest parts of the track to make. moar flings never seems to hurt though.

3. somebody is at their apex when the first comment is rabid saying "I Like Squirrels." nobody has hit their apex yet.

Get back to the roots of Line Rider and you'll see there's no 'better'. Therefore you can't gauge improvement. Every track is simply different.

People only hit their apex when they either stop trying new things, stop having fun, or no longer have as much time to make tracks

Improvement/What makes a track good is gauged by 1) others' opinions of perceived skill, commitment, and entertainment value and 2) the trackmaker's opinion of their own track.

Pretty darn difficult to judge what makes a track "better" than another besides public opinion, and even then it's different for each person so there's no absolute. You can't deny that some tracks are better than others for the vast majority of people (e.g. BS is better than Old People), but it's more of a fine grayscale that varies subtly and differently for each individual so some tracks will be greater for some people and others greater for other people (that's why both tracks always get votes in ToC polls)

EDIT: And I want to add that the individual is what matters to the trackmaker (or should be, anyway), not the majority opinion. One person who loves your track is better than a dozen who judge it as being better than another track without conveying any personal opinion.

However, if you're going to say "no tracks are better than any other tracks" then I don't want to see you post things like "could have been better" or "not your best" or "you've improved" because I will then be