The original plan was for Randy Orton to escape Unforgiven with the title, and continue on a long-term title reign. However, this reporter also noted that officials within WWE began pushing for an HHH win, and ultimately, got their way.
The rationale behind putting the belt on HHH is that WWE feels Randy Orton can be more effective “chasing” the title, rather than carrying the title. WWE does not feel Orton has gotten over enough, or carries enough momentum, to be a meaningful champion, so needs to develop the necessary heat by chasing the title and earning fan support, leading to a more climactic future title win.
A theory reported late last month was that HHH might have pushed for Randy Orton’s face turn as a way to kill Orton’s momentum and regain the title himself. While the series of events is somewhat accurate, most do not believe HHH had any interest in maliciously killing Orton’s character.