Just because a corporate operator takes a hit from losing a pilot on short notice does not mean they are poorly run. Many great corporate jobs only have 1, 3 or 5 aircraft. A staff of 3 pilots may be plenty for 1 airplane to provide a decent schedule.

Many corporate pilots develop close relationships with their owners and fellow pilots, and simply don't wish to bail with a 2 week notice and leave their fellow pilots to pick up the slack.
Maybe their owner is about to send them to a $70K recurrent training course next month and they are trying to be considerate and not burn a bridge.

Fortune 400 flight departments are not like the regionals that will hire any goofball who walks thorough the door. Decent corporate operators take time to hire the right person to fit their operation. Finding a new replacement for that one slot could take a month or more.

So an airline giving only a 2 week notice to attend class can create an uncomfortable situation for said pilot. Especially if he was told to expect a class less than a month away, then 3 weeks before they change their mind and give a date 2-3 months away.

Seems like the airline may be the ones with poor management and planning.