[OxygeN]

There are of course both quantitative, and qualitative factors to knowing if your improving, and to quickly go through some of them,

Quantitative :
Higher win-rate.
Utilize most of your resources.
Building the counters to your opponent unit mix
Building sufficient production structures.

Qualitative :
You feel more confident vs a specific match-up,
Positioning your units better, (eg. maruders around marines, roaches infront of hydras)
Doing more harassment.
Losing less from harassment.

Hope this helps!

Quick Comments

inFeZa:

good advice