DST is about the compromise between two reasonable scheduling systems: in one you use a 24 hour day with a clear landmark (noon, when the sun is highest in the sky). In another model you use sunrise as a natural beginning to the day.

Sunrise is a bit complicated, and in winter it compresses the afternoon more than many people would like. Also hard to build the necessary clocks. So we simplify things and make a compromise between the two systems, and we get DST.