AE Section Commit After option has impact on AET record value, will remove all the values.

Today I changed one of my AE Section Commit After option to 'After Step' just for testing as below:

After that, I found the AET record values all changed to null in the PeopleCode Action, which cost me much time to find out the reason...
After some testing, I remember that I changed that option...after changed it back, all worked.