What's fueling the red-hot IPO market?

Snowflake isn't the only debut this year to have a big first day and then pull back. CureVac, BigCommerce Holdings, Berkeley Lights, nCino and Lemonade all saw their shares soar before cooling off. How smart is it for the average investor to buy into an IPO at the open? Kathleen Smith, principal and co-founder of Renaissance Capital, joins "Squawk Box" to discuss.