Describe a specific, valid use case for employing a `PATCH` HTTP method within an OTP API, detailing what resource it would modify and why `PUT` would be less suitable.

A specific, valid use case for employing the `PATCH` HTTP method within a One-Time Password (OTP) API is to update the state of an existing OTP request resource, particularly when a user's verification attempt fails. An OTP API manages the lifecycle of One-Time Passwords, which are temporary authentication codes. A resource, in the context of an API, is an identifiable entity, such as an `otp_request`, exposed via a Uniform Resource Identifier (URI) that holds specific data and can be manipulated. For instance, an `otp_request` resource at a URI like `/otp-requests/{id}` might initially contain attributes such as a unique `id`, `user_id`, the actual `otp_code` (which should not be directly exposed or modified by clients), `status` (e.g., 'pending', 'sent', 'verified'), `expires_at` timestamp, and `attempt_count`. When a user submits an incorrect OTP for verification, the API needs to record this failed event. The `PATCH`....