You asked a clear question in Slack. By afternoon the thread has a meme, two side conversations, a "quick one while I have you," and a reaction from someone who cannot decide. The original ask is twelve messages up. The person who could answer marked the channel as unread and went to dinner.
A channel is a room. Rooms do not hold a single question still. That is not a moral failing of Slack. It is what a room is for.
The ask has to compete with the room
Every message in a thread is equally a message. Your decision request and a joke about lunch have the same shape: a bubble, a timestamp, a name. Respecting the reader's time is hard when the product is designed to keep them in the stream. They are not opening a letter. They are glancing at a room that will still be talking if they leave.
So the ask sinks. People reply to the latest line, not the first. A reaction stands in for a sentence. "Sounds good" attaches to whoever spoke last, which may not be you.
The reply mirrors the request. A request that had to shout over a channel gets a shout back, or nothing.
There is no signature on a reaction
A later argument about what was decided will be a scroll. Two people will remember two different messages. A green checkmark is not "I own option B." It is a pixel that meant "I saw this" to one person and "I agree" to another.
A decision request needs a closed list and a pick that can be quoted. Slack can carry that if everyone is disciplined. Everyone is not. The people you need across a company line are not even in the workspace.
Lift the question out
When the ask matters, take it off the stream. One recipient — or the one person who can pick — a briefing with the options, the rejected path, the assumption, a note you approved. They can answer tomorrow. The channel can keep talking without rewriting the question.
You can still mention the thread: "this is the write-up of what we started in Slack." You do not make the thread the system of record. The package is.
If they have no AI, they get email and a page. If they use a different assistant, they pull the same package. Nobody had to join the channel to do the job.
What Slack is still for
"Are you around for a five-minute call." "The build is red." "I picked B — briefing incoming." Coordination, not closure. The moment you need a sentence you can show in six weeks, you are no longer in Slack's genre.
If the thread already lost the ask, do not "bump." Write the page. Send it to the person who can answer. Let the room be a room.