If you donāt ask, you will not know the reason, it shouldnāt be down to attendance alone however, although given one of your parade nights is a Friday, I imagine you are there most Fridayās and using the weekends for studying. Although I appreciate some of the comments above about making time for study leave etc there will be some āold timersā that might not be on the same page. Although I agree education should be a priority, especially if you have an early Wednesday morning exam in your case however a Tuesday night break can be good for focusing on something different if not. As realistically being honest, as I was there when I was a cadet, what extra learning are you going to gain between 18:30-21:30 on a Tuesday that couldnāt be factored into the weekend/other mid week nights or free periods at school.
I also feel that a lot of cadets and I always have this chat with my cadets, put too much pressure on being a Cdt NCO, yes there is some organisational tasks however there is no expectation to do these outside of the Sqn (CWO maybe slightly different), and if you were promoted to a CPL and given a task, any associated project work related to that would be done when you were at cadets. Remember it is a hobby not a job.
Although the organisation is fantastic way to develop, by leaving (your choice or not) as I would say to a cadet in my squadron, if you leave now what personal opportunities will you miss out on. Do not under any circumstances use the leaving cadets as a threat (for a better term) as there are many other cadets on the Squadron and it would be simply accepted as its a shame but ok. If you want to better yourself as an individual do not run, politely find time to speak with the OC and ask what you can do to become a CPL and also ask how close/why you didnāt get selected this time.
Itās amazing how many OCās donāt know the names of many cadets or see what they do as they do all their admin at the Sqn and nothing in their spare time (whatās that many might say) donāt be a keyboard warrior and be afraid to say to your OC in a polite way, I have done X,Y,Z however just wanting to know what I need to do to become a CPL. Your OC might say, these guys did a Wing NCO course or a Silver Leadership course or it might be as something as simple as that.
As an officer, I have always made time to be on 1st parade (as well as finals obviously), regardless if the OC is busy so cadets can see a staff member that cares, I observe a lot of drill, activities, presentations and projects to provide feedback to the OC (I dedicate an extra night for admin tasks as well as other evenings and weekends on top of the parade nights) it is a 7 day operation, we operate very tightly within our NCO limits, sometimes it does mean only 2 CPL spots are available, however when a SGT or F/SGT leaves for Uni or ages out or we are successful in pushing a F/SGT to CWO it allows the pyramid to be filled upwards. If you just leave you will never know/