When I explain "learning ukemi" for beginners, I explain to them that it is not about learning how to fall or how to breakfall. If you are going to fall, then just fall, there is nothing to learn about it. Ukemi is not about falling though.
So what is ukemi? Here's an excerpt from an essay I wrote for my Yudansha exam (but I changed topic after I got stuck):
Let's first see how the word ukemi is written in Japanese. The word is written in two parts, uke and mi. The kanji for uke means receive, while the kanji for mi means the body or the person. In the dictionary, combining the two means being acted upon or passivity. But, in the martial arts world it is taken to mean as break falling.
There is always some type of ukemi in every proper martial art. It is taught either as a way to save oneself from injury when falling or could be taught as a manoeuvre in techniques.
Many do teach on being passive and receive the fall, as the meaning of the word, and keeping oneself safe at all times. Also, technically, there are many types of ukemi: falling and slapping on the ground, front roll, back roll, and even get back right on one's feet. From a mechanical point of view this is all correct, but so many get technical that one forgets about the actual force that drives the fall.
In Aikido, it is not only about the fall, but in learning and feeling the force that drives the fall.