Dynamic step activation (DSA) is a flow concept that allows steps to activate (or deactivate) steps later in the flow. It gives the end-user (or REST client) control over optional steps.
Example:
Using the DSA concept, an end-user may, for example, activate a Remember-Me Step by checking a box ("Keep me logged-in") on the login page:
In the example, checking the box activates the Remember-Me Step later in the flow.