The rest of the work is done with the bankers as they draft the S-1 along with information provided by the management team.
In terms of pitching the bankers, ours was during Covid so there was no travel, it was all done remotely, and given the large financing event that the IPO was, the amount of time invested vs the capital raised was certainly worth it.
IPOs open up liquidity for shareholders, early employees, also provides new avenues for the business to create financing for various activities as you are now seen as a premier partner with all of the major banks. Honestly worth the effort, so long as you continue to run the business with a long term mindset and don't give in too much to the quarterly pressure it's a huge plus.
Besides the obvious benefits to shareholders and early employees it also does open up a significant amount of opportunities when it comes to M&A, if are strategic with that, it can dramatically change the outcomes for your business.