What it means
A service team may finish a visit but leave no usable record, which makes billing, warranty and customer review harder. The gap measure identifies jobs whose required evidence is absent or incomplete.
A fictional cleaning firm bills 100 visits and five lack the agreed checklist or client confirmation, so its evidence gap is five jobs, or 5%, under that rule. Start with the agreement.
Some jobs need a signed report, others need readings, photos or a system log, and a generic attachment count cannot show whether the right proof exists. A fictional electrician who uploads three photos but omits the required test reading still has an evidence gap for that requirement, and a fictional technician who attaches a photo of an unrelated generator leaves the job flagged as missing relevant completion evidence.
Decide the population: jobs closed, jobs billed or jobs reviewed in a period. These denominators can differ if invoicing lags service, so a fictional company that completes 120 jobs but bills only 100 this month should not quietly use 120 as the denominator for a billed-job gap.
Connect evidence to the right job, site, asset and date, and check quality, not mere existence, because an unsigned photograph from another visit may sit in a folder without proving this service. The U.S. federal acquisition payment rules require proper invoices and supporting acceptance documentation for covered contracts, which is a jurisdiction-specific example of evidence tied to services, not a rule every private customer must copy.
A field-service evidence scorecard from CoSkip asks whether required proof, notes, context and sign-off are clear; it describes a directional review tool, not a formal audit or universal standard, and its useful lesson is to define evidence before measuring absence. Separate missing from weak evidence, since a blank signature box differs from a signed form with an unreadable note, and tag gaps by type and severity in a register.
Proof of attendance does not automatically show quality. A timestamp may confirm a technician arrived while the repair remains faulty, as with a fictional air-conditioner visit that has a geolocation ping but no cooling test, so the metric should not replace outcome testing or customer acceptance.
Review gaps before invoicing when possible, because prompting for missing evidence on site is easier than chasing it weeks later, and never fabricate a late signature. Some evidence cannot be safely reconstructed.
If a fictional inspector skipped a safety reading, the firm schedules the proper test rather than typing an estimated value into the form, and each gap needs an owner and deadline so jobs do not drift between operations and finance. Segment by service type, crew and cause, since a technician issue, a broken app and an unclear contract requirement need different remedies, as when a billing team sees ten incomplete reports from one route and operations fixes the mobile form instead of asking each customer to chase staff; protect private information, keep disputes and financial loss separate from the gap, and close a gap only when valid evidence or a documented exception is accepted while preserving the original missing state for analysis.
In practice
Real-world examples.
Example
Five of 100 billed visits lack required accepted reports. The billing team holds those five invoices until the missing sign-offs are obtained, and records which technician and route each one came from.
Example
A technician uploads photos of a repaired pump, but the required pressure test reading is missing. Reviewers log the job as incomplete evidence even though the photos exist, and the technician returns to take the reading.
Example
An offline form is synced with its original timestamp after a technician works in a basement with no signal. The office accepts it because the form shows when the work was actually recorded, and it is not treated as a backdated entry.
Formula
Calculation
Evidence gap rate = jobs lacking accepted required completion evidence / jobs reviewed in the defined period x 100. "Accepted" must have an explicit meaning, such as a signed report with the correct asset ID and the required test reading.
Worked example. A fictional maintenance firm bills 100 visits in a month and reviews all of them against its agreed evidence rule.
- Jobs with accepted evidence = 95, so jobs lacking accepted evidence = 100 - 95 = 5.
- Evidence gap rate = 5 / 100 x 100 = 5%.
- If the firm had completed 120 jobs but billed only 100, using 120 as the denominator would give 5 / 120 x 100 = 4.2%, which understates the billed-job gap.Case study
Seen in the real world.
In this fictional case, Harbor Service bills 100 maintenance visits. Ninety-five have the agreed report and customer confirmation; five do not. The gap rate is 5%. A review finds three reports were never submitted and two have the wrong asset ID, so the firm fixes its mobile form and checks the cases individually.
Watch out
Common mistakes.
- Counting any uploaded file as valid proof.
- Assuming missing evidence means no work occurred.
- Backdating a signature to make the gap disappear.
Questions
People also ask.
Does a gap prove service was not done?
No. It means required completion evidence is missing or insufficient.
What belongs in the denominator?
State a consistent population, such as billed jobs or closed jobs.
Can a late note fix it?
Only if it truthfully meets the agreed evidence rule; do not invent missing measurements.
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