Why are you required to brake now?

You are required to brake because of the motorbike. According to German traffic rules, when another road user is entering or crossing your path—especially at intersections—you must adjust your speed or stop if necessary to give way and prevent danger. In this case, the motorbike is waiting to turn onto the main road you are driving on; to allow the motorbike to enter safely and avoid a collision, you must reduce speed or brake. The van and cyclist do not require you to brake at this moment, either because they are not yet a danger or they must yield to you. Always be attentive to road users at intersections and adjust your driving to ensure safety.