Question About Preventing Degenerate Solution

[KarlXing]

Hi, thank you for making the code available and I'm very interested in your work.
When reading the paper, I have a question about preventing the degenerate solution. I really appreciate if you could help me.

So forward circle makes sure that latent code s has no unspecified information. But the degenerate solution is that latent code z might contain specified information.

I don't understand how reversed cycle prevented this problem. In an extreme case, s contains no information and z contain both specified and unspecified information. Under this case, same z with different s will generate same images and thus getting same z''. Reversed cycle cannot prevent this extreme case, right?

Please correct me if I'm wrong. Thanks!