Define “suitable” in business terms
A suitable enquiry is not simply someone who completed a form. Define the minimum characteristics that make an opportunity worth progressing. That may include service fit, geography, budget range, timing, authority, compliance requirements or delivery capacity.
Keep the definition short enough for staff to use consistently. If suitability requires a 20-field scorecard, the business will revert to intuition.
Separate quality from conversion
A good enquiry can still be lost through slow response or weak follow-up. A poor-fit enquiry can still convert if the business says yes to work it should avoid.
Track suitability and conversion separately. This prevents the team from blaming marketing for every lost sale or celebrating low-margin wins as proof of channel quality.
Use reasons, not just rates
When an enquiry is unsuitable or lost, capture a small set of reasons. Examples might include outside service area, wrong service, price mismatch, no response, competitor, timing or capacity.
Patterns in reasons are often more actionable than a single conversion rate. They can reveal a messaging problem, targeting problem, response problem or capacity problem.
Compare channels on downstream value
A channel with fewer enquiries may be more valuable if the enquiries are suitable, convert at a healthy rate and fit delivery economics. Avoid ranking channels by cost per lead alone.
A practical weekly view can compare suitable enquiries, response speed, quote or booking rate, win rate and average commercial value.
Protect the measure from hindsight
Write the suitability definition and loss reasons before reviewing campaign results. That reduces the temptation to change the rules to defend a favourite channel.
The aim is not statistical perfection. It is a stable decision rule that helps the business learn.