One big reason to prepare my own food is that I can make it the way I want. Of course some things can be added to those ready made meals as well to make them taste more the way I want. For example making them more spicy. But there is already something I don't like it's almost impossible to remove.
I rarely buy such meals. There are obvious benefits making your own, but the taste is one big thing for me. I usually only buy them if I know I wont have time to prepare anything for my self (or am feeling lazy).
I have my preferred brands to buy certain ready made meals. Usually a long process of trial and error trying out different brands and finding the one that best suits my taste. Sometimes that exact product happens to be sold out. I could of course choose something else, but when the idea of eating something is in my mind it's hard to change. So I have to resort buying some other brand.
As this happens so rarely I hardly remember what I have already tried preciously and judged not good. So often I end up having to eat something that I don't enjoy that much. It would have been better to choose something else to eat after all.