The Answer is manifold. One aspect could be how much information can be put into the BIM models that give a ROI in the operation phase. Another aspect can be to investigat ethe readiness of all stakeholders to talk about BIM goals before starting the project,
One suggestion could also be to distinguish between stakeholder groups in the assessment of BIM benefits: It makes a difference - especially when ROI calculations play a role - whether BIM is implemented in large companies or in SMEs.