Airbnb (ABNB) and DoorDash (DASH) will have to come out of the gate blasting financially as public companies, given the borderline insane valuations giddy investors afforded both on their respective IPO days.

In other words, with such heady valuations from the jump for the non battle-tested home rental and food delivery businesses — the Street will be expecting the sky and the moon from co-founders and CEOs Brian Chesky (Airbnb) and Tony Xu (DoorDash) on each earnings day for, well, perhaps the next five years.

Good luck living up to those expectations every three months.

“These companies [Airbnb and Doordash] will have to produce results that in fact meet or beat investor expectations,” Renaissance Capital principal Kathleen Smith told Yahoo Finance Live. “The bar is being set very high by just looking at the day one performance.”

You aren’t kidding about the wild one-day performances.

Airbnb finally opened for trading Thursday at $146 a share, dusting the initial public offering price of $68. The opening trade on Airbnb valued the company at $101.6 billion.

For some perspective on the real-life market mania, that’s more than the combined market caps for Airbnb’s established rivals Marriott, Hilton and Hyatt of $80 billion. That’s more than the $62 billion market for 112-year-old auto giant General Motors (which is sitting on some game-changing electric vehicle technology, as GM CEO Mary Barra recently told Yahoo Finance Live).

The market reception to DoorDash’s IPO on Wednesday was nothing to sneeze at either.

Shares of the food delivery service rose about 80% on its first day of trading on the New York Stock Exchange. While DoorDash shares gave back 8% Thursday, the company still sports a market cap north of $66 billion. That’s more than Burger King and Popeye’s owner Restaurant Brands’ $18.6 billion market value.

“There is a lot of enthusiasm about companies that are familiar to the mass consumer. DoorDash and Airbnb are very familiar names, and they tend to get a hotter reception when they come out,” Smith said of the fiery market debuts. “But the bottom line is these companies have to trade connected with the performance and the financial results. And so that we are going to see in the next couple of months if we can look back and say gee, they left so much money on the table or not. We’ll see.”

Why this could all end badly for investors in both companies — at least those chasing IPO-day momentum in the near-term — boils down to what Smith said about on sky-high expectations and financial reality.

Airbnb has posted $2.1 billion in cumulative losses since its creation in 2008. It reported $697 million in losses through the first nine months ended Sept. 30. Not only has Airbnb managed to never turn a profit during the pre-pandemic good travel times, when it may turn a profit post pandemic is anyone’s guess.