Lafayette
Colonel Lafayette was head of the British division of UNIT, during the time Dr Elizabeth Klein was its scientific advisor, and lasted three months in the role. He was known for being pompous and petty, and UNIT Central Control soon realised he was out of his depth and prepared Major Wyland-Jones to replace him. Relations with Klein were bad, with neither liking or respecting the other.
Lefayette would do anything to get his face on television (but, as he complained to journalist John Starr, reporters kept spelling his name wrong). When the Mind Leeches first appeared, he was too busy giving press statements to pay much attention.
There were no full invasions until the last days of command, when had to deal with interdimensional invasions caused by the Reborn Master; he also met "the Doctor" (actually the Master pretending) and was starstruck. The Master called him a complete idiot.
He was killed by the Skyheads after communicating with them. Within minutes, he was replaced by Wyland-Jones - rushed to London by Geneva's orders before Lefayette's death - and the new commanding officer was willing to insult the man's memory. (AUDIO: UNIT: Dominion)