11 national championships. Well, that may technically be true, but almost all of those were before 1948, with the majority before the Great Depression (for reference, Princeton and Yale each won 27 national titles before 1935). They have shared one national title since 1948, with Nebraska in 1997.

Years in which Michigan claims to have won a national title: 1901, 1902, 1903, 1904, 1918, 1923, 1932, 1933, 1947, 1948, 1997

Even in the Big 10, they haven't won the conference championship in a decade. Their bowl record is infamously atrocious. The truth is that Michigan hasn't been what it claims to be in a very long time. If it weren't for the one exceptional blip in 1997, they would be almost indistinguishable from most run-of-the-mill BCS/P5 programs since World War II. TV ratings and media hype have created an inflated persona for this particular program, most than almost any other. It shouldn't be such a surprise that they have struggled to attract top coaches to Ann Arbor (which really is a great town, BTW).