Interesting. My former company paid a huge amount of money to study what makes people come back to websites. The answer was strange. Faces had a huge impact. (What site does that remind you of?)
Secondly a feeling of accomplishment. Also, our application was a work based application. When we started showing progress instead of problems the usage doubled.
Our application was meant to read their data and give them a report. (original version gave a red highlighted report of errors, we switched to show what they were doing right, and added an error page they had to go to, it was strictly UI, no changes in functionality, just display) We doubled our end-users and customer satisfaction was known industry wide.
It is a long way to say, when you make people feel good, they come back. Being ignored doesn't make people feel good.