The two most important aspects of pumping are comfort and output. Sure, time is important as well, along with posture and ease of use, etc., but if you can empty and do it comfortably (we are referring to the nipple/breast), other inconveniences seem like, well, small potatoes.
Stimulation is what triggers a letdown
No Letdown,–>little milk.
The body doesn’t know what a pump is and so whatever stimulation is created becomes the stimulation the body responds to…..until further notice.
Depending on how long one has been pumping with incorrect and uncomfortable flanges, the uncomfortable feeling is engrained in the subconscious as the trigger for a let down. So when the right flange is used and comfort is reached, the body must reprogram itself to recognize this new feeling as one that is worthy of letting the milk go even though the intensity is less.
Close your eyes,
Drop your shoulders
Think about baby being what is causing the new, softer, lighter touch to the nipple
Have a Nursing session in your head, not a pumping session
So if new flanges are comfortable but output isn’t there just give yourself some time, you are almost there!