Why 'We Do Everything' Should Make You Nervous
The suppliers worth keeping are the ones who tell you what they don't do. I know that sounds backward. In eight years of buying parts for an automotive supplier, I've watched purchasing teams—including mine—reward the vendors who promise the most. We shouldn't.
I handle purchasing for a 220-person Tier 2 supplier. That means roughly $1.8 million a year across 16 vendors: stamping dies, fixtures, MRO supplies, and the Dayco ATV drive belts and Dayco idler pulleys that keep our plant's material-handling carts running. I report to operations and finance, which means I get blamed from both directions when a vendor overpromises.
The $14,000 lesson
In 2022, we brought in a new supplier that advertised 'full-service metal solutions.' Stamping, forging, CNC, assembly—their capabilities deck had 40 pages. I didn't fully understand the cost of that breadth until a $14,000 progressive die order came back with hole positions out of tolerance. The die needed three rounds of rework. Delivery slipped six weeks.
I still kick myself for not asking for their die maintenance logs before cutting the PO. The sales rep had an answer for everything (note to self: that's usually the warning sign). Finance didn't care about the excuses—they cared about the $9,000 in expedited freight and the four hours of line downtime.
That vendor wasn't lying, exactly. They could do stamping. They just couldn't do it well enough, consistently, at the tolerance we needed. Breadth isn't the same as depth.
The vendor who said no
Around the same time, we sent Dayco an inquiry for a small batch of 2010 Ford F150 alternator mounting brackets—a short run, maybe 300 pieces. Their engineering lead came back quickly:
At that volume, our tooling setup wouldn't be cost-effective for you. Here are two job shops who specialize in short runs, and here's what to ask them about tolerance stack-up.
Never expected the vendor who turned down our business to become our most reliable one. That response told me more about their quality system than any certificate on their wall. We later moved our plant cart fleet over to Dayco ATV drive belts and Dayco idler pulleys, and the failure rate on those parts dropped to almost nothing. Not because they're magic—because they only put their name on the parts they actually engineer.
To be fair, their pricing isn't the lowest we see. I get why buyers chase the cheapest quote. But the cheapest quote rarely includes the cost of the rework you'll do later.
The hidden cost of 'one-stop'
Total cost of ownership (i.e., not just the unit price but every cost that follows the part through your plant) is where the generalist supplier usually loses. A low stamping price means very little when you add:
- Incoming inspection time (usually 2–4 hours per lot for a new vendor)
- Rework or scrap (our average on out-of-tolerance lots runs about 8% of PO value—this is our own AP data from 2024, not an industry benchmark)
- Expedited freight to cover the gap
- Line downtime while you wait
The 'expensive' specialist who delivers in spec the first time is usually cheaper by the time the part reaches the line.
'But isn't consolidation more convenient?'
Yes. I get why one-stop shopping appeals—fewer POs, fewer calls, fewer vendor reviews. To be fair, consolidating our MRO orders saved our accounting team about six hours a month (this was back in 2023, before we split the categories). Convenience is real.
But administrative convenience doesn't fix a die that's 0.3 mm out of tolerance. And it doesn't help when you're on the phone explaining to your operations manager why the line is down.
Here's the comparison that finally made it click for me: you wouldn't ask a calculus tutor to explain why people steal catalytic converters. Different expertise, different questions. The tutor might have a theory, but you'd be better off asking a criminologist. Yet in procurement, we hand a supplier a drawing and assume they can pivot from idler pulleys to alternator brackets to custom enclosures without missing a beat.
What I ask now
Before adding any vendor, I ask three questions:
- What don't you do?
- What was the last job you turned down, and why?
- Who do you send customers to when it's outside your scope?
The answers tell me more than a capabilities brochure. A vendor who can name their limits has usually thought hard about where their process wins—and where it doesn't.
The bottom line
I'd rather work with a specialist who knows their limits than a generalist who overpromises. The specialist who says 'this isn't our strength—here's who does it better' is giving you free risk assessment. That's worth more than a discount.
So when a supplier tells you they can do everything, ask them what they do best. If the answer is 'all of it,' get a second opinion. The vendors who admit their boundaries are usually the ones still standing when the deadline hits.