But leaving recent history aside: the fact of the matter is that Tesla is now valued at 136% the market capitalization of Toyota, an organization that currently ships about 50x more vehicles each year than Tesla does.
The only possible way for Tesla to achieve earnings from car sales that justify this stock price* (on a reasonable time scale) is to build out their manufacturing capabilities at an unimaginable scale and pace. The amount of capital that this will require is vastly higher than anything Tesla has raised before. And since the period we're discussing is long enough that we can't predict global market conditions, Tesla may find themselves doing this remarkable build-out during a period where capital isn't easy or inexpensive to come by.
* I'm assuming here that the market cap of Tesla reflects some realistic theory about future earnings, and isn't just a massive and unjustified bubble. Which it probably is.
[1] https://www.theverge.com/2019/5/17/18629166/elon-musk-tesla-... [2] https://finance.yahoo.com/news/tesla-may-avert-bankruptcy-bu... [3] https://www.wsj.com/articles/tesla-shares-sink-as-musk-jokes...
Musk has also said that growth in his companies are mostly people constrained and not capital constrained. His companies can raise capital any time they decide it is a good idea.