Last time I managed a team, the worst employee was technically brilliant. He was a former professor at a good university. He basically went off and did his own

Last time I managed a team, the worst employee was technically brilliant. He was a former professor at a good university. He basically went off and did his own thing, mostly unrelated to what the rest of the organization wanted or needed. He disregarded corporate policy, including in ways which might have exposed us to liability. For example, we deal with highly-sensitive, regulated personal information. He copied files onto his own laptop, where he also downloaded and ran warez he found on sketchy web sites. That was the tip of a very deep iceberg. I think I spent more than half of my management time on issues related to him. He left for a different team within the org, and later, left the organization. He's now at a FAANG, analysing sensitive personal information. I'm not surprised he passed their interview process. There might even be a good spot for him there, but NOT dealing with sensitive, personal information.