Quality.
I will be quick to point out that what we sometimes refer to as bad quality is simply a different style of animation. Quality here is more than just the visual fidelity but also the execution, pace, timing, and sound design.
The saying ‘soup wey sweet, na money kill am‘ is especially true in this case. Making something taste good (or look good, in this case) requires some processes that just take more time, talent and money.