Harm was done by going forward; not only to himself but to his wife and children.
"Mallory had premonitions about what might happen. Before leaving for that fatal attempt on Everest in 1924, he visited Kathleen, the widow of Captain Scott, and confessed to friends he was in two minds about whether he should leave his own wife and small children in Cambridge. In a way many will recognize, he never quite made the decision himself but let others make it for him. The Everest committee were determined that their finest climber would be part of the team, and Mallory’s wife Ruth did not want to be seen to dissuade him from going."
And at the root of the tragedy it's implied lay technicalities yes, as Mallory didn't want to go with pragmatic complement George Finch again.
But the underlying culprit seems to be the apparent lack of choice he must have felt in context; boiling down all the way to Francis Younghusband and his goal to "conquer Everest" for Britain (not good old masculinity without skin in his game either btw).
"Now, it appears, Mallory had told the committee, as one of his deferring mechanisms, that he would not think of joining the new expedition if Finch was going; so they fired Finch to persuade Mallory, and he was left with little alternative but to prove he was a better climber on the day, whatever risks might be involved."