I've often heard corporate salespeople use the ABC (Always Be Closing) mantra, but Rob is so right ... for start-ups, it's ABT (Always Be Talking). And his comment about the conversations having a "goal" is perfect. You really do need to know what you're trying to learn before you start.
Ya, exactly. 'Always Be Closing' helps performance for small-value sales where there's only ever a single interaction with the customer and the purchase price is low enough that they can't be bothered to come back and harass you.
For anything which takes longer than one meeting/call (e.g. everything a startup does in the early days) or which has a high value, though, ABC is actively counter-productive.
Neil Rackham did an awesome job of debunking most of the myths about hard closing in 'SPIN Selling', which is the only book on sales I've ever gotten real value out of.