# When TAM has no eligible-account rule > The model multiplies a broad business count by a price without showing who could use the product. Diagnose the cause, choose a bounded correction and verify eligible account count tied to a reproducible scope. Source: https://saas-marketing.net/guides/tam-model-has-no-eligible-account-definition/ Topic: SaaS Market and Industry Data Type: guide Published: 2026-09-17 Last updated: 2026-09-17 Publisher: SaaS Marketing (saas-marketing.net) License: CC BY 4.0. Quote or republish with attribution and a link to https://saas-marketing.net/guides/tam-model-has-no-eligible-account-definition/ ## Short answer The model multiplies a broad business count by a price without showing who could use the product. Start with this check: Define the customer workflow, geography, supported requirements and exclusion criteria. The corrective action is to count the eligible population under a documented method and show uncertain assumptions. ## Key takeaways - Define the customer workflow, geography, supported requirements and exclusion criteria. - Count the eligible population under a documented method and show uncertain assumptions. - A large addressable market is not evidence of obtainable demand. - Review eligible account count tied to a reproducible scope. --- The model multiplies a broad business count by a price without showing who could use the product. The useful response is a diagnosis that changes a decision, not another report describing the symptom. Use this play with the research owner and the person using the estimate for a decision. The working evidence should include source method, market boundary and assumption table, with private or sensitive details removed from any shared example. ## Confirm the problem in the actual workflow Define the customer workflow, geography, supported requirements and exclusion criteria. Start with one representative case and follow it from the original action to the reported outcome. Identify where the observed behavior first differs from the intended process. A screenshot of a final dashboard can be useful, but it may hide the source record, a delayed update or a decision made elsewhere. Keep the unit of analysis explicit: a clearly defined population, period and value measure. The same label can conceal different populations or stages. Before comparing two results, check that they describe the same kind of work and have had a comparable chance to complete it. ## Separate the visible symptom from the cause Read the original definition before combining figures. Publication date, collection period and forecast horizon answer different questions. A market estimate can be useful without being directly comparable to another publisher’s number. The symptom in this case is specific: the model multiplies a broad business count by a price without showing who could use the product. Ask which piece of evidence would distinguish an operating failure from a measurement failure or a mismatch in the original plan. If the evidence is unavailable, record the missing source and its owner instead of treating the preferred explanation as established fact. ## A situation to work through Not every company in an industry needs or can adopt a particular operational workflow. This is an illustrative situation, not a reported client case. Record the equivalent evidence and assumptions for your own workflow. ## Choose the smallest useful correction Count the eligible population under a documented method and show uncertain assumptions. Keep the change narrow enough that the responsible people can implement and inspect it. If a correction changes several things at once, describe it as a combined operating change; do not later claim that one small element caused the whole result. Assign the correction to the research owner and the person using the estimate for a decision. Agree which artifact will show that the work is complete. An owner without an observable acceptance condition can close a task while leaving the original problem unresolved. A detailed checklist without an owner creates the opposite problem: the evidence requirement exists, but nobody is accountable for producing it. ## Preserve the important limitation A large addressable market is not evidence of obtainable demand. This condition belongs beside the recommendation because it can change the decision. It should not disappear when the plan becomes a short presentation or a status update. A software-revenue estimate and a broader customer-spending estimate may both be credible within their own definitions. Averaging them does not create a better answer. Explain the boundary and choose the measure that matches the decision being made. ## Verification worksheet | Review item | What to record for this issue | Owner | Evidence | | --- | --- | --- | --- | | Observed symptom | The model multiplies a broad business count by a price without showing who could use the product. | | | | Diagnostic test | Define the customer workflow, geography, supported requirements and exclusion criteria. | | | | Proposed correction | Count the eligible population under a documented method and show uncertain assumptions. | | | | Guardrail | A large addressable market is not evidence of obtainable demand. | | | | Review measure | Eligible account count tied to a reproducible scope | | | Download a working copy and follow the [worksheet instructions](/resources/#using-worksheets). Keep unknown facts visible rather than filling gaps with guesses. ## Decide whether to keep, revise or stop the change Review eligible account count tied to a reproducible scope after the agreed observation period. Keep the correction when the intended behavior is verified and the guardrail remains acceptable. Revise it when the diagnosis was useful but the intervention did not resolve the cause. Stop and reassess when new evidence shows that the original problem was framed incorrectly. Record what changed in source method, market boundary and assumption table. This gives the next review a stable starting point and prevents a definition change from being mistaken for a performance improvement. ## Related methods and next steps - [SaaS product ideas from recurring workflow problems](/guides/saas-software-ideas/) - [SaaS industry statistics: a source register method](/research/saas-industry-statistics/) - [Define the market before choosing a number](/courses/saas-market-sizing/01-define-the-market/) - [Pressure-test the estimate and present its limits](/courses/saas-market-sizing/03-pressure-test-and-present/) Return to the [saas market topic guide](/saas-market/), browse its [complete resource collection](/topics/saas-market/), or use the [working resource library](/resources/). The [primary reference](https://www.sec.gov/edgar/search/) provides relevant platform or methodological context; the diagnosis and example here are original editorial guidance. ## Frequently asked questions ### What is the first diagnostic check? Define the customer workflow, geography, supported requirements and exclusion criteria. Inspect the actual working record or customer path rather than relying only on a summary report. ### What should change after the diagnosis? Count the eligible population under a documented method and show uncertain assumptions. Record the owner and the evidence needed to verify the correction. ### What limit should the team keep visible? A large addressable market is not evidence of obtainable demand. A local improvement does not establish a universal benchmark or guarantee a commercial result. ### How should the correction be evaluated? Review eligible account count tied to a reproducible scope using a consistent unit and observation window. Keep the original evidence and record any measurement changes.