Smooth animation is mostly the in-between frames nobody notices. So is most good work.

The frames people remember are the poses, and the poses only work because of the invisible frames connecting them. Those in-betweens are the bulk of the labour and attract none of the attention. Almost every field has the same structure: a few visible moments resting on a mass of unglamorous work that nobody will ever name.

Look at your current project and find where you have been skipping the connective work. The transitions, the second drafts, the dull parts between the good bits. Spend one session only on those, and watch how much more solid the whole thing feels afterwards.