I sent a Christmas greeting to the structural engineer I work for thanking him for providing me with a steady volume of clear and thorough design sketches 95% of the time (nobody's perfetc). I mentioned that growing up I had no career ambition other than to be productive, and that he's been a big help in that regard for over 38 years. Here's his response, and I swear I wasn't fishing for compliments.
'You’re welcome (although my rating may go down to 90% after you receive today’s package). You have definitely achieved your ambition of being productive. DCU has been able to provide a superior product all these years due much to your efforts'.