Ihsan is more than temporary emotion during worship. It should inform attentiveness in prayer, honest dealings, keeping promises, and respecting others' rights.
عَبْد (servant) and عِبَادَة (worship) belong to the same semantic family and connect devotion to responsibility before Allah.
Compare two behaviors:
1. A person is honest under supervision but cheats in private.
2. A person remains honest publicly and privately because they regard themselves as accountable to Allah.
The second better reflects the lesson of Ihsan.