NPS gives you a number every quarter. A feedback board gives you a named person, a specific blocker and a date. Both are signals; only one tells you what to do on Monday.
NPS is lagging and lossy
By the time an account drops from 9 to 6, the decision to leave is often already forming. And a score with no attached request tells you sentiment moved without telling you which capability caused it.
Sample bias makes it worse: the accounts most at risk are the least likely to answer.
Votes are behavioural and continuous
A user who takes the time to write and upvote a request is telling you exactly where the product blocks their workflow. Multiple votes from the same account on the same theme is one of the cleanest churn precursors available.
Because it is continuous, you see the trend forming rather than a quarterly snapshot of it.
Use both, but weight them differently
Keep NPS for board reporting and benchmark comparisons. Use the board for prioritisation and for account-level risk flags.
The combination that works: filter open requests by accounts renewing in 90 days, then sort by weighted votes. That list is your retention backlog.
What breaks the signal
Anonymous voting. If you cannot tie a vote to an account, you lose the churn prediction entirely and are back to popularity contests.