Di Montezemolo, who took the decision to replace Brazilian Massa with Raikkonen following the
Italian Grand Prix,
said: "The relationship [with Felipe] was clear. He needed results and so did we.
"He did get some, but he was inconsistent, having some good races but not on a regular basis. It will be good for him to have a change of scenery."
It is not clear where 32-year-old Massa's future lies, but he is being linked with the 2014 Lotus seat vacated by Raikkonen.
Ferrari's decision to partner Alonso, 32, with the Finn signals a return to the policy last employed between 2007 and 2009, when Raikkonen and Massa competed on equal terms.
Either side of that period, with Michael Schumacher from 1996-2006 and then with Alonso for the past four years, there has been a clear number one driver.
Fernando Alonso one of the best - Di Montezemolo
Speaking about suggestions Alonso was not informed of Raikkonen's arrival, Di Montezemolo added in
Gazzetta dello Sport:
"We are not masochistic enough to take on a driver without informing Alonso.
"Fernando was always in the picture regarding the choice, taken partly because employing a youngster, in what will be a complex 2014 season, did not inspire confidence.
"In a nutshell, I wanted a driver who would not make me regret Massa [leaving]. What I ask of Raikkonen is wins, a consistent performance level and podiums and Alonso will be the first to benefit."
Singapore Grand Prix, day one
Friday 20 September: First practice at 10:55 BST on BBC Radio 5 live sports extra, plus live text commentary online from 10.30. Second practice at 14:25 BST on BBC Radio 5 live sports extra, plus live text commentary online from 14:00.
Singapore Grand Prix, day two
Saturday 21 September : Final practice: online live text commentary from 10:30 BST. Qualifying at 14:15 BST on BBC Radio 5 live sports extra plus live text commentary online. Qualifying highlights, 17:15 BST on BBC One.
Singapore Grand Prix, day three
Sunday 22 September: Race coverage at 13:00 BST on BBC Radio 5 live, and live text commentary online from 12:00. Race highlights, 17:00 BST on BBC One.
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.