Recusal is a touchy subject for government officials, for two principal
reasons. One, withdrawing from a matter can appear to constitute an
admission of misconduct. This is because so many people, and even
ethics codes, consider it wrong to have a conflict. Actually, recusing
oneself is a way of dealing responsibly with a conflict, and is the
opposite of misconduct.
Two, raising the issue of a conflict can disclose information the
official would rather keep personal. After all, the conflict involved
is between personal interests and the public interest, so some sort of
personal interest must be disclosed if a conflict is disclosed.