A major manufacturer’s law department has committed to its 250 or so law firms that it will pay their invoices within 30 days. While longer than the usual prompt-payment commitments, for which some firms grant small discounts so long as they are paid within ten days or less, the 30 day threshold is probably quicker than most departments achieve.
The commitment lacks passion, and I doubt it makes a whit of difference to the law firms. The more law firms run themselves like businesses, though, the more punctual payments may sway them.