Why do Lithium battery and electric car stocks seem to consistently start high and taper hard?

Understandably, electric vehicles is a hard industry to break out in, especially here in the US where adoption of the technology and infrastructure has been underwhelming, and there is a singular giant already filling much of the space that these companies are vying for. What I'm confused about, is why do these companies fall so flat? They obviously aren't Tesla and aren't enjoying success to the same degree that Tesla does, but at least in my area, Rivian vehicles are a regular sight. Nikola just got a pretty solid deal to sell 30+ trucks to a major US trucking company, and Microvast is one of the only companies of its kind with a real marketable product. How is it that these companies can trade so low compared to their industry leader? What is it that I'm missing? These companies certainly aren't as strong with their youth and associated hardships (such as debt) but these seem to have been undervalued for years with no sign of relief.
$Rivian Automotive (RIVN.US)$ $Nikola (NKLA.US)$ $Microvast (MVST.US)$ $Tesla (TSLA.US)$