Scope creep is the gradual expansion of work beyond what was originally agreed, without a corresponding change in fee or timeline. It erodes margin quietly, because each addition seems small while the cumulative effect is significant. It is one of the main reasons profitable engagements become unprofitable.

Scope creep never arrives as a big request. It arrives as a series of small ones, each too minor to push back on, until the engagement you priced at a healthy margin is losing money. The defense is a clearly defined scope at the start and the discipline to name additions as additions, before they accumulate.

Example:

Eight small out-of-scope requests, none worth arguing about individually, can consume the entire margin on an engagement.

Why is scope creep so hard to prevent?

Each individual request is small enough that refusing feels petty. The damage is cumulative, so it is invisible until the margin is already gone.

How do you protect against scope creep?

Define scope explicitly at the outset and name out-of-scope requests as they arise, rather than absorbing them and discovering the cost at the end.