Time investing is a procedural tactic used to create a perceived value in the negotiation itself. Getting parties to spend time on the deal increases the cost of walking away, rebooting the process with someone else, or doing nothing.
Negotiators may run the clock before hitting you with an ultimatum. Statistically, you are more likely to agree to a deal if you have time invested in the transaction[iii].
The negotiation process itself is an investment in time and money. The best way to handle this is to know how much it costs, and when returns are diminishing. A well-run company may know how much using one network configuration costs every day versus going with a lead bidder, so you must keep an eye on the clock and the cost of the negotiation and go to close as the clock runs short of cost/benefit minutes.