To ensure a rotation occurs over time, the execution must be yielded back to the Unity engine each frame. This is achieved by moving the logic into a Coroutine, which allows the use of yield return null to pause execution until the next frame. By tracking the elapsedTime, we can interpolate between the start and end rotations linearly.

1. Cache the starting rotation using transform.rotation before entering the loop.
2. Calculate the specific target orientation using Quaternion.Euler or a target reference.
3. Initialize the elapsedTime float to zero to begin the transition tracking.
4. Create a while loop that continues as long as elapsedTime is less than the desired duration.
5. Increment elapsedTime by Time.deltaTime in every iteration to maintain time-consistency.
6. Update transform.rotation using Quaternion.Lerp, passing in the start, end, and the normalized value of elapsedTime divided by duration.
7. Use yield return null inside the loop to allow Unity to render the current frame before proceeding.

Additional Tips

• For a more polished feel, wrap the interpolation ratio in Mathf.SmoothStep(0, 1, t) to add easing to the start and end of the rotation.
• Always apply the final target rotation explicitly after the loop finishes to correct any floating-point inaccuracies accumulated during the elapsedTime calculations.
• If you need to stop an ongoing rotation before starting a new one, store the Coroutine in a variable and call StopCoroutine before initiating the next sequence.