Their study attributed failure of ITIL adoptions to many factors including lack of management commitment, work instructions, realistic goals, momentum, and process owners, as well as problems with time and staff management. In studying the most important factors for successful ITIL adoption, Iden and Langeland [2010] used a Delphi study of the Norwegian armed forces to rank the factors important to successful ITIL adoption. Their study validated the findings of Hochstein, Tamm, and Brenner [2005a] and Pollard and Cater-Steel [2009], concluding with a ranked list of the most important factors: managers at all levels must have ownership in the introduction of ITIL; senior management must formally make the decision to introduce ITIL; and key personnel should be identified and involved in the design and improvement of processes.