Budget cycles are often use-it-or-lose-it, so teams with remaining allocation have an incentive to commit spend before the quarter closes, pulling many purchasing decisions — including AI initiatives — into the same final weeks.

Security review, compliance and stakeholder alignment, and integration scoping should all start well ahead of the deadline, so that only contracting and final sign-off remain in the final weeks.

A reasonable evaluation runs six to eight weeks, covering shortlisting, a parallel security review and proof sprint, and a final contracting period — though this varies by organization size and regulatory requirements.