The spike that looks like a win.
Spam and bot leads push the conversion count up and the cost per lead down, so the account trains itself on bots while every indicator reports success. Blocking the source afterwards stops new junk; it doesn't erase what the bidding already learned from it.
The form fill arrives late in the journey.
6sense's 2025 survey of nearly 4,000 B2B buyers puts first contact with a vendor at 61% of the way through the buying journey. The platform treats that one form fill as the conversion and optimises toward producing more of them.
Source: 6sense, 2025 Buyer Experience Report.
Hours, weeks, months.
Google can spend up to twice a campaign's average daily budget on a given day, capped at 30.4 times it over the month. After a change, a bid strategy can take up to three weeks to calibrate. Medicare's open enrolment runs 54 days, 15 October to 7 December. Whether the leads were any good arrives from the CRM weeks or months later, often after the season it belonged to.
Sources: Google Ads Help, spending limits and learning period; Medicare.gov, Open Enrollment.