Why write about consistency? This is something that has been brought to my attention after giving a number of classes, sessions, and has also been raised as a question to me multiple times.
I'm writing about consistency in the context of giving G-spot vaginal massages and approaches to build up and, finally, orgasm.
Commonly, the traditional way of giving a G-spot orgasm is to utilize either the index and middle finger, or the middle and ring finger to access the G-spot. Both are fine as long as you and your partner are comfortable with it. (For those curious about the G-spot position, here is a snapshot taken from a rather descriptive piece found on imgur)
Where does consistency come in? Commonly, many partners, in their enthusiasm, and sometimes, education from porn, perform a "come-hither"/upwards lifting motion as fast and as hard as they possibly can. This can be seen in bursts of intense activity which is difficult to sustain. While such an action may be conducive to rapid edging or being a finisher/prelude to a big orgasm, it usually ends up leaving the lady frustrated if the partner is unable to keep up the consistent rhythm all the way towards the end.
While this may differ from individual to individual, it is more important, in my opinion, to be able to maintain a consistent rhythm for a longer period of time. There are some similarities to playing music here - it's not about playing all the notes as fast as possible, but about playing them on time, and consistent with the tone and pace of the score. Many have given feedback that they prefer their partners take on a slower, longer and more drawn out, more *consistent* pace to any vaginal stimulation.
Tip: Having music in the background to guide one's tempo or simply moving to a beat/tune in your head, results in a more relaxed form of G-spot massage that enables one to keep a sustained pace of action - one that eventually brings your partner to climax. DO pay attention to feedback from your partner, be it verbal or via unspoken body language (e.g. breathing, clenching of fingers, curling of toes, bucking of hips, etc.).
As always, approach the massage with an open mind and have a fun experience together!