How can management instill a sense of urgency without destroying instrinsic motivation?

The way you write, I understand that you talk about an IT startup. This simplifies things a little.

Why? Because programmers have a special ability to keep themselves motivated. The opportunity to program, and the programing itself, are one of the biggest rewards for them.

What is the main de-motivator for a programmer? Well, everything stupid is a strong de-motivator. So the main jobs of the management at this stage are:

1. Create a flexible project strategy, keep the objectives clear all the time, adapt based on the feedback from the programmers. Track the work done, do not allow the programmers to get creative about what can be done, keep the project on track.
2. REMOVE STUPIDITY. Do not make rules that de-motivate people.

and then...

3. The small things: comfortable, big-enough desks, comfortable ergonomic chairs (not necessarily expensive), enough monitors for the work at hand, whiteboards and whiteboard markers...
4. Meeting rooms. There are never enough.
5. OPEN SPACE OFFICES ARE ALWAYS HATED BY EMPLOYEES!!!
6. Good to have: small kitchen, some rest area (no noise, not even keyboards allowed, but maybe some bluetooth speakers), maybe some recreation area (ping-pong, table football...).
7. Do NOT promote under-quality people as managers! Do not promote people as mangers just because they have good technical skills! They might have terrible people skills...
8. I am sure that the list can continue, but these are some of the biggest motivation killers.

Examples of stupid rules:

• strict (hated) clothing rules;
• strict schedule; (this does NOT imply work-only-when-you-feel-like-it, but being "late" for 10 min should not be treated as the end of the world)
• insane punishments for small-ish issues;
• heavy bureaucracy; at my workplace now we have to make requests written with blue ink on white paper, written by hand, with no mistakes!! Any mistake means you have to write everything again, until someone somewhere gets happy and satisfied.

I am aware of two ways that seem to kind of work:

• having them own a product in production, which helps by providing a short feedback loop, and associates the reward of seeing it work in prod to the fast and ugly path ; and

• having them work on things that will greatly help other employees (either because it is required for the other employees to complete their work, or because it greatly improves their workflow), where the reward is social.

If the goal is to get the product developed enough to extend the life of the company, these two things don't help if the assignments are artificial.

Putting me in charge of product X wastes time if I don't have the skills necessary to own the product. I have seen this fail when they thought each developer should spend x hours a month as part of the help desk. We spent those hours hoping we wouldn't get a call or a ticket.

The assignment to work on feature X should be part of the planning process. Assigning it to a developer should be based on skills, work load, and need; not as a way to motivate somebody.

If the owners of the company know the urgency, but the developers aren't moving in a way that helps the company; then the issue is with the layer(s) between the owners and the developers.