Could be tied up in investment accounts (401k, 529, etc). Don't forget that the 2 million net worth includes some of the house, and you can't pay off the house

Could be tied up in investment accounts (401k, 529, etc). Don't forget that the 2 million net worth includes some of the house, and you can't pay off the house with the house and still keep it. ($2.4 million house - $400k mortgage = $2 million net)