The root problem is that knowledge exists only in people's heads, not in the system. The solution is to convert "what you're already doing" into searchable records in real time: customer preferences, historical quotations, key contact points, and special requests should all be entered into the system as work happens, not added retroactively. This way, new team members can review the system to understand the context without relying on word-of-mouth from experienced staff. Specific practices include: adding notes in customer records to document key discussions, keeping version records of every quotation and PO, and tying discussions and agreements to the corresponding documents instead of scattering them across LINE groups. Once these habits are established, staff turnover has much less impact, and the company truly owns its customer relationships rather than borrowing from individual networks.