- Is the task stable enough to justify continuing ownership? A one-off feasibility question may need a bounded engagement; a core production capability may justify a durable internal role.
- Can we supervise the specialist? An expensive hire without access to domain reviewers, usable data and a product owner can still be blocked.
- Which work is recurring? Separate model experiments from operational incident response and customer integration.
- What must remain independent? The person optimising a model should not be the only authority deciding whether the final test passed.
- What happens during absence or turnover? Require documentation, reproducibility and access held by the company.
This is a make-or-buy decision about capabilities, not a contest between salary and a consultancy’s headline quote. Compare the work covered, duration, supervision, tooling, benefits, recruiting time and the opportunity cost of diverted staff.