Because he was the first and only president to serve 2 nonconsecutive terms
The President can only serve up to two terms in office.
They can serve only two terms.
Grover Cleveland is the only US president to serve two non-consecutive (or two interrupted) terms of office.
They can serve two terms.
Franklin Roosevelt
He is the only president to have been elected for two nonconsecutive terms: 1885 and 1893.
To be married in the White House* He was obviously the only president to serve two separate terms in Office.
Franklin Delano Roosevelt
Franklin Roosevelt was the only one to serve for four terms as president.
None have served exactly 10 years.
Grover Cleveland had that distinction.