Ethic: new prudent man rule

from text book: “A trustee’s fiduciary compliance is based on whether the investment turned out to produce total returns that increased the wealth of the trust beneficiaries”, the answer said it is not consistent with new prudent man rule. But as I read the rule, can not find where it violate. any suggestion? Thanks.

I think the key part here is “turned out to”. If the investments were appropriate and its looses money, no problem.

also isnt the prudent Man rule the old rule? The new one in prudent investor rule

compliance is judged at the time the investment was made