Well basically companies give dividends once they have met...

Well basically companies give dividends once they have met significant resistance to growth. In the case of a2MC there are strong growth opportunities so giving dividends at this stage would not be beneficial to investors or the company.

At this stage it is clear that investors would achieve a much higher return leaving it invested in the company than you would as a dividend. I am oversimplifying this but would you rather a 5% dividend or 30% growth? Normally companies slowly increase their dividend from 1-2% but hopefully you understand my point. There are also considerations IRT franking for dividends so you may end up losing a significant percentage to the tax man depending on the situation. So when you look at the compounding effect this has it would be far superior to let a2MC maximise your return for you at this stage.

To answer your question though it depends how long it takes for a2MC to reach market capacity not only in US and China but in other potential markets. Additional funds may be used to support suppliers or possibly change the framework at a later stage. Either way it allows for flexibility without going into debt during this growth stage. The below quote is from a post by @SmugLex

If you attended the the last AGM Jayne H. spelt it out in nouncertain terms. She and the BOD have no intention whatsoever of a dividend orshare buyback in the short or medium term future.

There are plenty of companies that offer dividends but a high growth stock at the level of this company will be very hard to find.