My understanding is that an ideally priced IPO should not move much from the opening price in the near term. If it pops it means they left money on the table. If it drops, then I am not sure what the implication is exactly? Now I think SpaceX is massively overhyped, but is the share price returning to IPO opening not just a sign that the banks accurately estimated something?
Your bank will get a ton of orders from institutional investors of how many shares they want at a given price. You will have a preference as to which investors you want on your cap table. Almost all of those investors value your stock less than the "pop price" (which includes the investors you want on your cap table). So you'll need to target the IPO below the "pop price" so you get them on your cap table.
You're probably picking investors based on how likely they'll let you stay on the board / CEO and if you think they're just going to dump the stock during the IPO (which would be bad for it's price).
So (unlike the SpaceX IPO) you're going to sell relatively little shares to retail who will buy at any price which during the opening days will cause it to spike as the demand (in nominal dollars) per share is beyond the IPO price target.
> but is the share price returning to IPO opening not just a sign that the banks accurately estimated something?
Sure they estimated something. But there's a ton of different things that can be estimated.