Last week I visited one of the popular investing message boards, where investors were debating the latest news from electric vehicle (EV) maker Tesla Inc (Nasdaq: TSLA).

Feelings about Tesla are as polarized as today’s political viewpoints. Both bears and bulls are absolutely convinced of their case, and they can be insufferable when arguing it. But this overconfidence is resulting in some risky behavior by investors.

Investors Make Their Case

The bearish case for Tesla is it has burned through an incredible amount of cash without turning a profit, the quarterly losses continue to worsen, and many competitors are beginning to appear in the market.

In addition, a number of executives have recently left the company, and this week Bloomberg reported that Tesla is producing fewer than 750 cars a week. Last summer Tesla had predicted that it would produce 5,000 cars a week by the end of 2017.

Tesla CEO Elon Musk has repeatedly overpromised and underdelivered. He has assured investors that there wouldn’t be a need to raise more capital, only to announce afterward that more capital would need to be raised.

The bullish case for Tesla is simple. Elon Musk is a visionary (“carnival barker” — according to the bears), EVs are the future of transportation, and Tesla is poised to dominate that future.

There are a couple of gaping holes in the bull case, but there is one thing on which we can all agree. Tesla shares have risen by more than 700% over the past five years. As far as the bulls are concerned, their faith has been generously rewarded, and it is thus hard to shake. To the bears, they say “Doubt all you want, but Tesla is making me rich.”

Risky Behavior

This faith was amply demonstrated in a story told by one of the message board posters. The person claimed to be an unemployed MBA caring for his ailing mother. Nevertheless, he had placed his entire savings into Tesla stock.

The poster claimed that he had already grown a four-figure investment into a five-figure investment, and fully expected that to grow into a six-figure investment in Tesla as the company realized the wildest fantasies of the bulls.