That's not necessarily true, though. Consultants often work hourly on contracts, which means that you're typically punished for being efficient as you won't have as many billable hours.

This generally means that you're better off being less efficient while still meeting the deadlines/goals.

Of course, there's a tradeoff since proving yourself to be more efficient than expected could result in more work etc, but it's not as clear cut as being rewarded for efficiency.