We ran Bob Dole against clinton in 1996 because it was his turn. McCain probably got the nod in 2008 because primary voters in Iowa and some of the other early states decided it was his turn. The GOP nomination for president should no longer be some kind of lifetime achievement consolation prize.
I am not sure why that happens but on the R side it is usually the case. McCain got the nod in 08 after he ran in 00.
Reagan got it in 80 after running in 76
Nixon in 68 after barely losing to Kennedy in 60
Bob Dole in 96 after running a couple of times
Bush Sr also ran in 80 then got it in 88 though obviously the man was VP
Ike and W were probably the only two in recent history that got it first time out. Of course W had the benefit of his fathers name which may have helped
perhaps we Rs just like familiarity or something.