/assign has three targets, and picking the right one is the difference between completion numbers that mean something and completion numbers that quietly don't.
To a person
/assign @name sends the course to one individual.
Right for: remedial training after a mistake, role-specific material for someone whose situation doesn't match a channel, catching up someone who joined before a course existed.
This is a snapshot, and that's appropriate here — you're assigning to a specific person for a specific reason, not describing an ongoing population.
To a channel
/assign #support sends the course to everyone currently in that channel.
Right for: role-specific training. Support processes to the support team, sales enablement to the sales channel, engineering practices to the engineering channel.
The reason this works better than a list of names is maintenance. A list is correct on the day you make it and stale within a quarter — people join, move teams, leave, and nobody updates it. A channel is maintained continuously by the people closest to the team, as a side effect of normal work, because membership determines who sees the conversation.
So the assignment tracks reality without anyone curating it.
Check the membership first. Channels sometimes contain observers — a manager, a stakeholder, a bot — who'll be assigned training they don't need. And someone who covers the function occasionally may need the training without being in the channel. Usually the proxy holds; take thirty seconds to confirm it does for yours.
To everyone who joins from now on
This is the one that fixes onboarding permanently.
Right for: onboarding sequences and company-wide policies — code of conduct, security awareness, expenses.
Without it, someone has to remember to enrol every new hire. That works until it's a busy month, and then a new hire silently gets nothing. The gap surfaces months later, usually when someone asks whether everyone completed the security training.
With it, the sequence runs whether or not anyone noticed the person started, whether or not the person who normally handles it was on leave. It also survives that person leaving the company, which is a common and quiet failure.
Reminders come with it
Assignment includes reminders, delivered in the same thread as the unfinished module — so someone can be reminded and finish in the same thirty seconds rather than being sent somewhere to act.
That's a meaningful difference from an email reminder, which adds a task rather than removing one.
Check the population, not the percentage
The most dangerous reporting error in training isn't low completion. It's 100% completion of the wrong population.
If a course was assigned to a list that missed three people, /progress will show everyone finished, and it'll be true of everyone who was assigned. The gap is invisible because those three were never counted.
So when you check coverage, look at who's in the population first. /progress returns live completion by team, so it's quick to confirm the people you expected are actually there — before someone else checks for you.
A practical pattern
Company-wide policies: assign to #general plus everyone joining from a date forward.
Role-specific training: assign to the relevant team channel.
One-off or remedial: assign to individuals.
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