Stopping at the verbal agreement
Most process mapping ends when the buyer says yes. The steps after that point, security review, legal, procurement, purchase order, signature authority, routinely consume as long as the evaluation did.
Accepting an estimate instead of a history
Two weeks is what people say. Asking how long it actually took last time produces a different and far more reliable number.
Missing the calendar
Monthly committees, financial year ends, audit periods, and holiday seasons all move dates in ways that are entirely knowable in advance.
Keeping the map private
A plan the buyer has not agreed to cannot slip visibly, because nobody on their side is watching it. Shared, it becomes an early warning system.
Not asking, because it feels intrusive
Questions about how things work here are welcomed. Questions about who has power, or pressure for a date, are not. Sellers frequently avoid the first because they have been told buyers dislike the second.