Ask HN: Why do tools like customer.io abandon self-serve after their Series A?

Why can startups never hold true to the principles that they started with?

When I first discovered customer.io I was the most excited person ever. I had finally found an email marketing system that felt designed for the data-savvy marketer. With a good analytics plan you could create amazing workflows. Building, editing, and previewing emails felt straightforward and intuitive. Signing up was easy and there was no need to talk to anyone. In two weeks the whole system was fully operational.

Pricing wasn't cheap, but felt fair. I didn't feel locked into a long term contract and could scale pricing based on true usage of the product.

I was so stoked about them that I'd bring it up regularly with co-workers and give demos for how we set up our system.

THEN IT HAPPENED...

I don't know if it was their Series A or a change in leadership, but everything started to change...

(1)the price hike based on contact count and not actual email usage (2) the stray Account Executive started reaching out to connect (3) the "forcing" onto an annual commitment plan (4) the disappearance of any way to just sign in and test the product (5) the annual AE call with fake promises to get the signature

We're leaving. I'm done. Rant over.

So the question I keep landing on: is there any company that has made it through this transition without gutting the product that earned them their early users? I want to be optimistic about Posthog and Resend, but I've been here before.