Why Approval Workflows on Slack DMs Don't Work

Slack, LINE, Teams, and other chat tools make startup communication fast. They are excellent places to ask a quick question, discuss context, and bring the right people into a decision. They are poor systems for running approvals.

The problem is not that a chat message cannot contain the word “approved.” The problem is that the decision is separated from the request record, supporting evidence, authority rule, status, and later reporting.

As the company grows, this gap creates follow-up work and operational risk.

Discussion and approval are different jobs

Discussion is exploratory. People ask questions, share opinions, and change direction. An approval is a controlled event: a defined request is accepted or rejected by a person with authority at a known time.

A strong approval record answers six questions: what was requested, by whom, with which evidence, under which rule, who decided, and when.

A DM thread rarely answers all six without manual reconstruction. Attachments may be replaced. The final scope may differ from the original message. An emoji may be interpreted as consent. Another approver may not see the conversation.

Chat hides the queue

When requests arrive through direct messages, every approver has a private task list spread across conversations. Requesters cannot see whether work is waiting, being reviewed, or blocked.

This leads to repeated follow-ups: “Did you see this?” “Who has it now?” “Can you approve today?” The company pays for the same coordination several times.

A workflow creates a shared queue with status, owner, age, and deadline. Chat can still notify the approver and link directly to the request, but it should not be the only place the request exists.

Authority becomes inconsistent

Startups often begin with founders approving everything. Later, managers receive authority by department, category, or spending threshold. If the rule lives in habit, requests are routed based on who happens to be online.

A workflow makes authority explicit. Purchases below one amount may go to a department head; higher amounts may also require finance or leadership. Vendor onboarding may require security review only when the vendor handles personal data.

The system should select the correct route using request information and preserve the decision trail.

Evidence is difficult to retrieve

Imagine reviewing a software purchase six months later. The invoice exists in accounting, the proposal sits in Drive, security questions were discussed in a channel, and approval was a DM response. Understanding the decision takes detective work.

A controlled request should link or store the proposal, budget, vendor record, security outcome, comments, and final approval together. The audit trail does not need to be complicated. It needs to be complete enough that another person can understand the decision.

This is especially important when employees leave. The company should not lose operational memory with their chat history.

Notifications are still valuable

Moving approvals out of DMs does not mean abandoning chat. Use chat as the attention layer.

A good notification states what needs a decision, the amount or risk, the due date, and a link to the full request. Reminder messages can be sent when the request is pending. The final outcome can be posted to the requester or relevant channel.

The decision itself should be recorded in the workflow so permissions, timestamps, and evidence remain consistent.

Design the minimum approval workflow

Begin with one request type that creates frequent follow-up, such as purchasing, vendor onboarding, leave, equipment, or contract exceptions.

Define the request fields. Include only information needed to decide or fulfil the work. Define the routing rule and who can act as a delegate. Set a target response time and reminder schedule. Decide what happens when the approver is unavailable.

Use simple statuses: draft, submitted, under review, approved, rejected, and completed. “Approved” and “completed” are different: approval authorises work, while completion confirms it happened.

Record comments and changes. If the amount or scope changes after approval, decide whether the request must return for review.

Roll out without slowing the team down

People resist workflows that add fields without removing work. Start with a short form and prefill known information. Make the pending queue easier than searching chat. Send useful notifications rather than excessive reminders.

Pilot with one team for two weeks. Measure submission quality, response time, and the number of follow-up messages. Ask approvers which information was missing. Improve the form before extending it.

Publish a clear rule: discussion can happen in chat, but a decision is official only when recorded in the workflow. Leadership must follow the same rule or adoption will collapse.

What success looks like

Requesters can see status without messaging the approver. Approvers have one queue. The correct authority receives each request. Decisions include evidence and timestamps. Operations can report pending, approved, rejected, and overdue work without reading conversations.

That is not bureaucracy. It is a small amount of structure that protects speed as the company grows.

To design your first approval flow, configure Workflow & Approvals in the system builder. You can also read How Much a Custom Back-office System Costs in Thailand before planning the implementation.