I think the balance
@Revoltingest was referring to is related to the employer maximizing profit. It's not about a consideration of the employee's interests. He's referring to the wage that generates the maximal profit for the employer, which can be too low to attract enough quality workers and higher than it needs to be to do this, which cuts into profits without any return for the extra wage expenditure.
Consider restauranteurs that can't get enough staff to sell as many meals as his customers would buy if he could get those meals out to them. He needs to choose a wage that attracts the staff he needs without making the business unprofitable if possible even if he gets them, that is, the lowest wage they will work for. That's the balance.
It's analogous to the problem of setting prices to maximize sales profits. Suppose a widget costs $5 to make, and at a sales price of $9, one can sell six units, at $10 five, and at $11 four. The optimum profit is at $10 (5 items at $5 profit each =$25, whereas 4 at $6 profit and 6 at $4 profit only generates $24 in profit). It a balance between charging too much and too little.
Notice that neither of these analyses is considering the employee's or the customer's preference, which are highest wages and lowest prices. The balance isn't between these entrepreneurs and the employee/customer. It doesn't consider them at all.