Broken dataflow

Dear all,

I've attached a pipeline that behaves in a way I don't understand. Maybe someone will be able to explain me.

The enclosed protocol is divided in two part:
- the top section is the pipeline that I don't understand,
- the bottom section is the same pipeline slightly changed that behaves the way I want.

If you could have a look and tell me why the first one does not do the same as the second one please.

Thank you