If you scale a track so that the Result take is longer than the current take’s duration (shown in the Action timeline), the Result track may not play the entire take. It may start playing in the middle of the track or end before the entire edit finishes playing. This happens because the timeline only plays between the Start and End time codes on the Action timeline.
To correct this problem, resize the Result take by changing the values in the Start and End time code fields in the Transport Controls window. You can also click Sync Take/Edit Start & End in the Motion Blend Options pane, or F-click in the Action timeline.
Changing the duration of the Action timeline adjusts the Result take’s Start time code to where its data or animation begins, and its End time code to where the take’s data or animation ends.
You can also automatically resize the Result track by selecting Tile All Cuts and Ghosts, though this also moves the cuts. See Tile All Cuts and Ghosts.