Dance music moves in 8, 16, 32 and 64-bar blocks, all in 4/4. Landing every arrangement change on a phrase boundary is exactly what keeps a track danceable and lets a DJ blend it with the next one.
Beginners break this without realising — a 7-bar section or an early change throws off the count and makes the track awkward to mix. Count in multiples of 8 and every transition falls into place.