In my experience, quality control becomes the hardest part very quickly.
At small scale, it’s easy to manually vet sites, anchors, content quality, and placement context. Once you scale, consistency drops unless you have very tight processes. That’s usually when footprints, weak sites, or over-optimized anchors start creeping in.
The second challenge is relationship fatigue. The more you scale, the more you rely on outreach partners, vendors, or publishers and keeping those relationships natural and diverse over time isn’t easy.
Scaling link building isn’t really about “getting more links,” it’s about scaling judgment, which is much harder to automate.