I've never understood why "just doing it anyway" was a fair argument when you do not have a choice over the thing you have to work on, but that it isn't when yo

I've never understood why "just doing it anyway" was a fair argument when you do not have a choice over the thing you have to work on, but that it isn't when you have a choice in doing something yourself. If what you do is a hobby, you are certainly able to give it up for another one if you aren't happy when doing it, or if it isn't "just your thing." But arguably, it being "not your thing" could just be because of your insecurity and unwillingness to conquer adversity, and thus giving up on something you don't "want" to do but do not stop thinking about regardless would be the wrong decision. That process of getting over your insecurity could take weeks or months or years of time, beyond just trying it a few times before declaring that it's not truly an interest of yours. For that matter, why do some genetic disorders reliably correlate with having only a set of narrowly defined interests, or no persistent interests at all? What does an "interest" even mean at a biological level? Are we always in control of what we are capable of caring about and acting towards, separate from what we merely tell ourselves we want?