Creating a chronology of an ancestor's life can serve many purposes. One is to see time periods when there is no information on the ancestor? Do you have a five year gap in records on an ancestor? Some gaps cause more concern than others--eight years between the 1860 census enumeration and a 1868 death is not probably a huge concern.
Selling property in location A in 1851 and then first appearing in another location in 1859 should make you wonder where he was between 1851 and 1859.
Unexplained gaps of time when one event indicates an ancestor might have been thinking about moving or might have just moved should get the research wheels turning in your head.