I feel like when anime is discussed in some circles people have a tendency to equate “good animation” with “animation containing many nice looking stills”. I do believe an animated sequence can be aesthetically pleasing or artistically intriguing primarily on account of the merits of its still image quality, for example, a simple panning shot of a sufficiently well drawn background can certainly be considered beautiful. However I take issue with the fact that some will specifically praise such shots as “good animation”, when, in actuality, the aspects of the shot which they are attributing its “animation” quality to have little to do with the “animatedness” of the shot. The term “animation” specifically refers to the process (or result) of creating the illusion of continuity and motion by sequencing static images over time. When one treats “animation quality” as a term that simply refers to the quality of the stills used in the sequence, the fundamental part of what makes it “animation”, the illusion of continuity and motion, is simply ignored. If you were a person who, rather than watching animations normally, stepped through the sequence one frame at a time and judged each still distinctly on its own merits, you wouldn’t be able to come to a conclusion about whether the sequence is animated poorly or not because what you are analyzing at that point is, by definition, no longer animation. By extending this logic you can see how ridiculous it is when people present a single frame from an animation and try to use it as evidence that the sequence as a whole is “poorly animated”, as they aren’t actually discussing animation at all. In cases like this if you really wanted to you could use this kind of evidence to claim that the sequence has “ugly stills” or “bad character/background art”, but even this type of argument typically won’t be very useful or interesting to most people, as when consuming animation very few people will spend much consideration on individual frames, as it’s their relationship, flow, and collective presentation that make the animation what it is.
Fundamentally, an animation is not simply a set of distinct frames, but a narrative formed through the continuity of relationships within a sequence of frames, and should be judged as such.