The everyday trigger is an employee asking to attend a course that falls partly or wholly within working hours. A trainee accountant needs three days for an ACCA exam sitting, a junior solicitor needs release for the SQE, or a warehouse supervisor wants to take a forklift instructor qualification the company is happy to sponsor. In each case you need the dates fixed in writing so the rota, the handover, and payroll all reflect the same reality. The form is also the natural home for the fee and repayment terms when the employer is footing the bill, because development conversations rarely get the paperwork they deserve until something goes wrong.
It earns its keep just as much when the answer is a qualified yes. Perhaps you can release the employee for the exam but not for the full revision week, or you can fund the course this year but need a two-year repayment commitment in return. Recording a conditional approval cleanly is far better than a vague nod that both sides later remember differently. The same applies to refusals: a statutory time-to-train request must be answered on proper grounds, and a written decision protects you if the employee challenges it.
One edge case worth flagging is the apprenticeship. Apprentices have a contractual and funding-linked entitlement to off-the-job training, and study leave for them is governed by the apprenticeship agreement rather than ordinary discretionary leave, so the standard form should be adapted rather than used blind. A second edge case is the employee who is also on long-term sickness or a phased return; here study leave can interact awkwardly with fit note restrictions, and the request should be checked against the Equality Act 2010 duty to make reasonable adjustments before being approved.