When should you think about using a message queue in your app?

hey everyone ive been thinkin a lot bout decoupling services and handlin async ops. message queues like RabbitMQ or Kafka seem like a common solution for this. but im curious, whats the key indicators or specific scenarios where youd say, yep, time for a message queue. is it purely bout scaling, or are there other benefits like fault tolerance or simplifying complex workflows that tip the scales. lookin forward to hearin your thoughts and experiences