Data decay

Also called: List decay, Contact data decay, Data degradation.

Every list starts going stale the day it's built. The US Bureau of Labor Statistics reported median tenure with a current employer of 4.1 years in January 2026, and 3.0 years for workers aged 25 to 34, so named contacts move on regularly. Businesses close too: BLS found that of private-sector establishments born in March 2013, the survival rate fell 20.4 percentage points in the first year, and 34.7% were still operating ten years later.

For local business lists, closures, moves and domain changes matter more than job changes, because the address you want is often a shared inbox. Listings change as well: Google says Place IDs can become obsolete when a business closes or moves, and recommends refreshing ones older than 12 months.

Decay shows up as bounces, wrong phone numbers and messages to businesses that no longer exist. It's also why old bought lists are risky: abandoned addresses can turn into spam traps.

The fixes are simple: record when each field was collected and checked, re-verify emails before a send if the last check is more than about a month old, and rebuild lists from the source rather than patching them once they're more than a year old.

Example

A list of 1,000 contractors built two years ago is re-verified. Dozens of domains no longer have mail servers, and a few hundred more addresses need checking again. Rebuilding from Google Maps also finds businesses that opened since.

In Leadraft

Each email carries its check date (verified_at), and each business its first-seen and last-seen dates. Monitors repeat a search on a schedule and deliver only new businesses.