we sent two surveys to an owned list (B2C) 1 year apart. response rates tanked the 2nd survey. for context:
we utilized pretty much the same invite copy/design and same raffle
users did NOT have received the survey twice. we ensure there was no overlap
we didn't investigate this, but a good follow-up analysis would be to compare the sign-up sources for both cohorts. it's possible for the 2nd survey, we brought in more customers that were from low quality sources (e.g., sweepstakes)
if it put my consumer hat on, I'm getting WAY MORE request for survey / feedback year over year (airlines, food service, customer service, retail, etc.). I wonder if you're seeing survey fatigue at-large