Qualifications

Every task belongs to a job — a category of work such as cutting, assembly or finishing. A builder is qualified for some set of jobs, and may only be assigned tasks in those jobs.

Why the dropdown is empty

This is the single most common setup problem. If the Assigned To picker shows no one, nobody is qualified for that task’s job. The pickers filter to qualified builders precisely so you cannot assign work that will be rejected.

A builder with no qualifications at all appears nowhere. That is usually an unfinished setup rather than an intent.

Setting them

Qualifications are managed per builder, against your job list. Add a job to a builder and they immediately become available for tasks in it.

QC is separate

QC assignment uses a different rule: the builder must be a lead or have can self-QC set, in addition to being qualified for the job.