Aiming for your bedside table to be level with or up to 10cm below your...

https://amumreviews.co.uk/should-bedside-tables-be-higher-than-the-bed/

Aiming for your bedside table to be level with or up to 10cm below your mattress-top is the sweet spot for comfort. This keeps your glass of water or phone within easy reach without feeling like you are digging into a deep pit