Is shareholder wealth maximisation goal a short or long term goal?

It's supposed to be a long term goal; but in the current markets short-term prices can raise stock values and get manager bonuses so they may bet tempted to go for more short term goals. Same thing for anyone preparing to sell their business and, for example, retire. Short term profits might get you a higher sal price, but the new buyer might find that that was at the cost of long term profits. For instance you raise short term profits by producing cheaper quality stuff at the same price, but lose customers for new owner down the road.