Malcolm Andrieshyn Explains the Conditions That Will Make Preserve UVs Not Work, and How to Easily Fix it so it Does.
With Maya preserve UVs is a helpful feature. That is when it works. The setting seems to work on simple objects, but quite often fails on more complex things. That doesn’t mean that you should ditch preserve UVs and write it off as useless. Watch this short tutorial from Malcolm341 for the “ah-ha” moment of understanding for why the preserve setting fails.
Andrieshyn shows exactly what happens in the UV editor when the setting fails. Understanding the issue automatically leads to a very simple fix. Malcolm shows how to detach and arrange the UV shells so that overlapping UVs no longer interfere with the preservation setting. Ah-ha!