Is Motion Tracking limited to fairly smooth motions?

Chances are, there was not a very distinct pixel to track. Match Move works best with a "corner" where pixels change color or have high contrast. If you don't have a point like that at the center of a track, find the nearest pixels like that to the center of the track and use the offsets to match to a "softer" point.

PS - In all the time that Match Move has been available (and that is the entire time I have been using Motion [13 years]), I have always found it much faster to just manually track points. It is very rare that you have to go frame by frame. If motion to be tracked is smooth, you can usually just keyframe two or three points over time. Adjusting "drift" points between the beginning and end become just a matter of making simple drag & reposition actions as you move the playhead around to "check" the track. I'm usually (but not always) done manually tracking before Analyze Motion would have finished.

It's a very good skill to have. One of my techniques is to halve sections. Set a position and keyframe on the beginning and end, then split the difference, set a keyframe in the middle. Then in the quarters... etc. Don't go frame by frame or in one direction only. You want to avoid setting keyframes (accidentally) too close together in time until you have to!

Learning to manually track is really helpful particularly when track points go **behind** some other part in the scene. Eyes on is the best way to approximate locations... automatic trackers have no idea how to recover, and dealing with an automatic track that "goes off the rails" is easily 10 times the work (and time!) and you end up doing the work manually, anyway.

Also -- an "outlandish" example!

Create a Bezier line - click one point on one side of the screen and one on the other. Move the playhead to the beginning and align one end point to starting position. Move the playhead to the end of the animation point and move the other end point to that position. Now move the playhead from the beginning an follow the track point. Add Point wherever you need to change the direction (can be any amount). Add a Motion Path behavior to the object that tracks. Set the Speed to Custom. You don't even have to set *any* keyframes -- that parameter is already keyframed from 0% to 100% automatically. Move the playhead and move the speed parameter to keep your tracking object aligned. The result is typically quite smooth and accurate. (You also have access to bezier smoothing between points).

(this is 10fps...)

The cut-in-halves method described by fox is the most intuitive one (as exemplified by mark Spencer here https://www.youtube.com/watch?v=Z8vieSB3Ngo) but I would add maybe some complementary advice, i.e spot the particular frames where the target to be tracked shows obvious articulations in its moves (change of direction, sudden acceleration etc.). This is generally the first thing I do, then cut each of the obtained sections in subsequent halves.

I personally obtain relatively good results with automatic tracking in Motion, but I may use several analyze motion behaviors over the course of one tracking instance, i.e whenever the tracker gets lost. I know you can correct a tracker's position, but I find it more convenient to start afresh with a new behavior taking over the previous one.

The last example given by fox is very interesting as automatic tracking would have a hard time here, absent a clear and stable background.