After a single carrier missed three consecutive commitments, the logistics lead doubled the supplier base overnight. Volume split 50/50. The next quarter, both carriers raised rates — neither had the volume to justify the old discount, and the "resilience" move had quietly become a cost increase. The second carrier didn't lower the risk. It lowered the leverage.
Resilience and scale pull in opposite directions
In transport, rate is a function of volume. The more you give one carrier on a lane, the better the price, the faster the capacity, the higher the priority when capacity is tight. Diversifying inevitably reduces that volume on the primary lane — and with it, the very commercial terms that made the relationship worth having.
So diversification is not free resilience. It is a trade: some rate and priority, bought in exchange for not being hostage to one supplier. The job is to spend that trade where it pays, not everywhere.
Don't split evenly — split by lane criticality
The mistake is treating every lane the same. A lane where a miss costs a production line is not the same as a lane moving slow-moving MRO. Yet teams often apply one diversification rule across the board.
A better map:
- Critical, capacity-constrained lanes — keep a strong primary, add a pre-qualified secondary held in reserve, not split. The secondary exists for surge and failure, not for daily share.
- Stable, competitive lanes — here, a real split (say 70/30) is affordable because multiple carriers want the volume and the rate doesn't hinge on one relationship.
- Low-value, flexible lanes — single source is fine; the risk of a miss is small and the savings from full volume are real.
Resilience is not the number of carriers. It is having the right carrier ready on the lane where a miss would hurt most.
Protect the commercial terms when you do split
When a lane does warrant a second carrier, the contract design matters more than the split:
- Negotiate the primary rate against the full lane volume, then grant the secondary only the overflow, so the primary's discount survives.
- Build a "right of first refusal" or capacity-hold clause so the primary keeps priority when the market tightens.
- Set clear hand-off rules: the secondary should be pre-integrated (EDI, tracking, SLA), not a name on a list pulled out only in a crisis.
A team that keeps the primary at 80% and the secondary at 20% on a competitive lane gets most of the resilience at a fraction of the rate cost — because the primary still clears the volume threshold.
The APAC wrinkle
Across APAC, carrier markets differ sharply by corridor. A regional framework that dictates one global split ignores that a lane in one country may have three viable carriers while another has one. Local procurement judgment should set the split; the center sets the principle (protect leverage, pre-qualify backup, integrate before you need it).
What good looks like
One regional shipper we know holds 85% with a primary on most lanes, keeps a pre-integrated secondary at 15%, and reserves full dual-sourcing only for the two lanes where a miss stops a plant. During a capacity crunch, the primaries protected them; during a rate review, the volume held the discount. They bought resilience on the lanes that needed it and kept leverage everywhere else.
The line to remember
A second carrier is insurance, not a default. Buy it on the lanes where a failure is expensive, and don't let the premium erode the rate you already earned.