What is a reason many retail portfolio managers outsource decision-making to third-party money managers? Review Later All portfolio managers utilize an internally built model as it is built specifically for your clients. Developing investment models in-house is often expensive, difficult, and time-consuming for portfolio managers. It is always cost-effective to outsource compared to internally managing investment decision-making. Portfolio managers are equipped with large teams and expert analysts to research investment opportunities that allow for better investment decisions and ultimately more satisfied clients