These two are fixed signs, both are stubborn, both do not want to make compromises, both want things to turn their way. The aquarius one is the calmer of the two, more cerebral, and therefore prone to discuss the issues. Taurus, another fixed sign, and aquarius hang better together because they are down to earth, realistic and pragmatic. They will sit down and discuss. In the other hand, leo being fire, all emotional and a bit "arrogant" and with scorpio, the water fixed sign, being double emotional with explosive character, these two are harder to deal with. With these two you argue and fight a lot. The whole "My way or the high way" does not work on another fixed sign, that person would just leave. Fixed signs together make relationships harder. It's all a matter of recognizing the stubborness and ensuring that both make compromises, not just one of the two.