When merging onto a motorway via the **acceleration lane**, it is essential to **accelerate to reach the appropriate speed** at the end of the lane. This is because:

- **Appropriate speed**: When entering a road, it is crucial to adapt to the speed of the vehicles already in circulation. This prevents becoming an obstacle and ensures a safe and smooth merge.
- **Safety**: The maneuver must be performed without endangering other vehicles. Accelerating to the appropriate speed allows for a safe integration into the traffic flow.
- **R.S.M. safety rule**: This rule emphasizes the importance of observing, signaling, and executing the maneuver at the correct speed, ensuring no danger is caused to other drivers.

Therefore, accelerating to reach the appropriate speed at the end of the acceleration lane is essential for a safe and efficient merge onto the motorway.