The bottleneck decides the delivery promise

The model

System output is constrained by the limiting resource or dependency. Adding capacity elsewhere does not remove that constraint.

Apply it to a deal

A 45-day implementation may depend on one specialist integration team, one security approval or one customer data milestone. That bottleneck sets the real schedule.

Commercial consequence

If Sales prices the deal as though capacity is abundant while the bottleneck is scarce, margin and timeline risk rise together.

Repair the constraint

Sequence work differently, reserve capacity, phase the scope, change the date or make the dependency explicit.