If your downline decides to cease engagement with the site (i.e stops upgrading) then your income is impacted. It's a constant battle to keep recruiting new members into your downline and hope they see the value in the program to upgrade. Often though if they then can't recruit into their downline they may then stop their upgrade payments, since they aren't getting the commissions that could facilitate that upgrade.

It's great if everyone can make the commitment to upgrade, but it rarely happens that way for most people.