Ann: Change of Director's Interest Notice - Van Der Made, page-22

Several reasons!
Probably a Tax bill.
He may want to pay down a loan.
He might just not like borrowing money and prefers to pay CASH for something.
Two years ago a similar thing happened and I asked the CEO at the AGM why he sold a small holding of his shares.
His statement was " My wife wants a new house and I don't want to borrow the money" He then said tongue in cheek said "Would you like to tell my wife she can't have the new house?" I know his wife.
I said "NO, I totally understand" and half the room broke up laughing.

One percent of his holding is nothing. He can spend it on whatever he likes.