Bugs, then they lost all my data
Wonderful product. Was one of my favorites, even though it had tons of bugs in it's first year, was happy to pay.
Then one of those bugs broke my account. Customer support is unresponsive / slow / sometimes just closes your ticket and doesn't bother responding to basic problems like "I can't update my payment details".
Then they lost all my data. So, yeah. Wonderful product, until I had to deal with Pipefy's support team, and they lost all my data.