As an agency, we are often invited to pitch to clients and invariably many of them require a design element to be included. Though it is a standard requirement for clients to gauge whether an agency is capable of producing good design, and in some cases the outcome may be completely based on the submitted design.Here are some reasons why judging a creative pitch purely on the mock-up designs may not help you choose the best design agency for your organization:1) The pitching agency is unlikely to have the full business case just by reading an RFQ and/or a meeting. With the number of bells and whistles that go behind customer experience websites, no mock up can include the right mix of navigational tools or personalization call outs that will ultimately be added on with the use of a CMS or marketing automation tool.2) It's done under pressure. Admit it. No agency is likely to have free design resources that can spend up to 7 to 10 man days (yes, that is how much time we estimate good design with all the dynamic objectives is likely to need) for a pitch. The presented designs are usually done under pressure and can never be the best work of the agency (trust me on this one!).3) You are likely to never use that design... ever. For the last 50 projects won by us, only 2 ever used the design we submitted in the proposal and that too not in its original avatar. No surprises here. Design requires time, business flow and integration with tools.Yes, mock-up helps you judge the agency. Whether they have talent. Can they walk the talk and so on. However, evaluation weightage to be given to design should range between 20 to 40 percent of the total evaluation criteria (personal recommendation!) and one must question the design, dig under the surface to understand the thought process to better understand the agency's overall experience and capabilities.And as the old adage goes, do not judge a book by its cover.Note: the thoughts are the authors' own and not representative of the organization.