Keyshot7 export avi file is so perfect small, why larger when to Gif?

[artact]

When Keyshot7 export an avi file, it is so small with perfect quality, such as this avi is only 534Kb.
But when i use GifCam record it to gif format,  why it is larger when converted to Gif format and quality is worrse?

• How to convert the video to gif format with a good quality?
• Why avi quality is better than gif but size is smaller?

Here are the converted gif files and original avi file:

[jasonbaldwin]

They're two completely different file types. You can search for the difference in compression in video and still images to learn more, but because of how each frame is compressed, a GIF and an AVI of the same sequence of frames are always going to be comparatively unequal.