I've been getting frustrated with my 2012 macbook air running el capitan.
My trackpad no longer registers clicking in the sense of a 'regular' quick click. Out of frustrated, I started applying more pressure and that would often work but after some more experimenting, I discovered that it's not a pressure issue, but a delay issue.
With a 'quick click' I can get maybe every 5th click to register. However, if I only my click down for almost a second, it registers nearly every time. (turns out that when I was using the 'lots of pressure' technique, I was also prolonging the length of the click, hence I erroneously thought it was an issue of pressure.)
I haven't been able to find this particular issue mentioned. Anyone have any theories and based on the description, would this be more hardware or software related?