How to assign cost to “avoidable requirements creep”: A step towards the waterfall's agilization

Scope creep is a major risk in fixed price projects. It has been suggested to distinguish between so-called “avoidable creep” and “unavoidable creep” where “avoidable creep” results from stopping requirements engineering (RE) effort too early e.g. for cost-saving reasons. However, no suggestion has been made how to assign cost to “avoidable creep” to quantify the consequence of too early stopped RE effort and to get that type of creep managed or even considerably reduced. From our experience in real and large fixed price projects, we derived a suggestion for solving this problem as soon as possible. The suggested solution has not yet been tried out in practice. However, with this paper we would like to begin a discussion about the suggested solution, and whether it could solve the problem of valuating “avoidable creep”, could thereby reduce both the customer's and the supplier's risk in large fixed price projects and, as a side-effect, serves as a step in converging pure waterfall and pure agile procedures.