10 meters can deliver worldwide DX on a handheld sized antenna and a handful of watts. The catch is that it only works when the ionosphere cooperates, and that is not often.
17 and 12 meters were added specifically to stay contest-free, and that quiet has made them two of the most pleasant, underrated bands in the entire HF spectrum.
Stuck between the reliability of 20 meters and the volatility of 10, 15 meters gets overlooked. It shouldn’t be.
6 meters earned its nickname honestly. It behaves like HF one day and VHF the next, and nobody can fully predict when it will do either.
The low bands reward patience, big antennas, and staying up late. Working DX on 80 or 160 meters is genuinely one of the most challenging and satisfying pursuits on all of HF.