A chap I used to work with did that, or almost. Damned infuriating. He'd put the tea bags and milk into the cups then switch the kettle on. Now being somewhat temporally challenged he'd often forget what he was doing ("concentrating on my work" was often his feeble excuse). So fifteen minutes later he'd go back to the kitchen and pour the hot water in. Then he'd bring my cup over to me containing a pale grey, but hot, drink of something that was almost but not entirely unlike a cup of tea.
What I could never fathom was that occasionally we'd have coffee and he'd never put the milk in first whether it was filtered or instant.