There were high expectations because, contrary to reports of his demise, Paterno had a tremendously strong program. His recruiting mistakes hadn't quite surfaced yet. People complain about the dark years and wonder why Joe was allowed to continue. It's actually pretty simple:
1. Proven track record
2. Unbreakable fund raiser, which also distracted from his time with the program
3. His ability to recognize problems and course correct
4. His proper evaluation of the talent on the roster and when to expect improvements
In hindsight Joe was absolutely the best person to lead the program out of the dark years, and he did it with resounding success.
It's funny, people point to 2001-2005 as the dark years. I look it as 97-01 when he was making his recruiting mistakes.