> If Twitter was prepared to make a higher offer, why didn't they?

Why should they? They have a fiduciary duty to get Instagram for as low a price as possible; nothing about 'begging', they weren't even told about the higher time-sensitive offer (which are just two parts of the price to be negotiated...). They were told Instagram didn't want to sell at all, which is more than a little bit different from 'we think FB will pay more, do you disagree?'.

> The people familiar with the negotiations said Twitter executives were shocked that they had not been given an opportunity to present a counteroffer. They said Twitter was prepared to make higher offers.