all dances

As a dancer, I can say that for me, it all depends on the style of choreography more than anything else. Some styles are just more natural for me while others might be technically easy, but take all of my focus and concentration on the first few attempts just because it isn't a way I am accustomed to moving. For me this often happens with hip hop dancing just because is often such a large number of small, bound-flowing movements and contractions in such a short time and it's usually very fast-paced. I am very used to lots of quick, bound-flowing movements in other styles, just not hip-hop. I have always found classical ballet to be the easiest to learn but the hardest to master. If I do not stay in practice, I can be thrown back a notch or two within a few days. This does not happen to me with any other form of movement, and since my dances rely very heavily on classical ballet technique it is something I have to work on all the time. Modern is usually relatively easy for me, so sometimes I do it in pointe shoes to add an extra challenge. I have never done ballroom except for one mini lesson in college. This all, of course, depends on the dancer, what they're accustomed to, on how good the instructor is, on the style of dance (sometimes the style of the style!) and even the floor being the right surface can make a difference in execution.

Personally, I feel that the modern dances are easier to learn but on the other hand, the traditional and classic dances, such as ballroom, are easier to execute. And definitely, it depends on the person who is learning and executing the dance.