Some big businesses are criticized for fcoucusing on short-term
perfromance at the expense of long-term expsense of long term results.
Why would a firm that strives to maximize stock prices be lesss
subject to an overmphasis on short-term results than one that
maximizes profits?

I could use an answer tonight if at all possible. Thank you

Certain high up executives are paid extra based on the year to year
profit of the company.  If simple profit in 1 year is their goal then
they will likely buy cheap machines and give less benefits to
employees (that is oversimplified, but definately the case) in order
to make their 1 year profits higher.

An executive who's goal is to raise the value of the stock in the long
run (perhaps with stock options) will be more likely to buy quality
machines that will last and will give good benefits to the employees
in order to retain the top notch workers.