I heard this once, not sure where, I think it was Simon Plant. But I like the concept. It’s about being kind to someone, instead of being nice to someone.
For example.
If you give constructive feedback, being candid and honest to someone, even though it’s not the best thing to hear. Is the kind thing to do, allowing them to grow!
The other option is to be nice, give them a big smile, pretend nothing happened and tap their back.