I have recently noticed that one of my coworkers writes his surname partly in hiragana when writing by hand.
This strikes me as odd, because his surname doesn't have multiple readings (to my knowledge) and is made of relatively simple kanji. He always writes it in kanji when typing. (For reference, the name is 桑野 and he writes it as 桑の)
Is there any reason someone would do this, and is it common? Or is he just being lazy?