Stablecoins get a lot of attention, but most of the excitement is built around the first half of the problem: the part where they move quickly, settle instantly, and feel like a better version of traditional rails. That part is true. It’s also the easy part.

The harder part is the second tail, the part of the distribution where most of the industry never looks. This is where currencies behave unpredictably, liquidity shrinks as soon as you add size, and seemingly “stable” flows disappear when the real world pushes back. It’s also where every stablecoin FX business either becomes real or quietly breaks.

At Devcon this year, this contrast was obvious. Most conversations were about blockchains, cross-chain routing, interoperability, unified liquidity layers. Important topics, but all focused on the rails. Almost none addressed the real bottleneck: the markets those rails land in.

You can build perfect infrastructure, but if the local FX environment doesn’t support your settlement, the infrastructure doesn’t matter. Faster bridges won’t create buyers for emerging market currencies. Better wallets won’t reduce volatility. Chain abstraction won’t stabilize a corridor whose banking system only clears on specific hours or changes requirements without warning.

The second tail is about everything people assume technology eliminates, but never does.

Some friends were running a fast-growing EM FX business. You have strong traction, customers lining up, and stablecoins give you a way to compress settlement times dramatically. Revenues look good. It feels like you’ve cracked something.

Then reality hits the parts of the system that are not onchain.

The OTC desks you rely on don’t have real depth. They clear small tickets easily, but size exposes structural weaknesses. A six-figure ticket suddenly takes hours to settle instead of minutes. A seven-figure request reveals there is no liquidity behind the quotes at all. Some counterparties vanish entirely (not with dramatic fraud, but simple disappearance, the kind that happens in environments where regulation is unclear and counterparties operate informally.

In one operation I studied closely, these failures weren’t rare. They were routine. Treasury exposure swung multiple percentage points in a single afternoon. Routing flows between countries sometimes required multiple intermediaries because no single desk could take the other side directly. Internal reporting showed that a significant percentage of volume got stuck not because of blockchain limitations, but because the last mile of the FX leg didn’t have real market depth.

Eventually, investors looked at the business, saw over a million in monthly revenue, and assigned it a value of zero. The revenue existed, but its foundation didn’t.

This is the second tail: the part that collapses when the operation grows faster than the market structure supporting it.

You can see the same patterns across most EM corridors:

Below five-figure sizes, depth feels normal. But once you push past that, the order book thins sharply. This creates a cliff effect: everything works until it doesn’t.

Intraday movements of 3 to 8 percent are common in certain EM currencies. A “flat” position is only flat if your counterparty exists at the end of the day.

As more players enter a corridor, everyone competes for the same demand, quoting tighter spreads is easy, settling those spreads consistently is not.

An AML requirement shifts, a settlement window closes, a preferred partner gets offboarded by their bank overnight. No amount of onchain optimization can fix that.

The first and last legs (where money enters and leaves the real world) determine success. That’s where the frictions live, and they don’t disappear because something is faster onchain.

These patterns show that the challenge is less about technology and more about the structure beneath it.

There’s a subtle trap in this space: early wins look convincing. Emerging markets are full of demand, especially from businesses that can’t use banks effectively. They show up fast, they move aggressively, they validate your idea in days, not months.

But they don’t tell you whether your model works at scale. They only tell you that there are people who want to move money quickly. (You already knew that)

The real test happens when you try to serve customers who need predictability, not improvisation. When size increases, volatility hits, regulations tighten and when a corridor breaks and you need a backup that doesn’t rely on a phone call.

A model built on contacts collapses as soon as the contact cannot solve the problem. A model built on speed collapses as soon as the market demands consistency. And a model built on spreads collapses as soon as spreads compress.

What survives is infrastructure, not improvisation.

Stablecoins are not the full solution, they are one piece in a system full of moving parts.

The FX legs matter, local rails matter, treasury exposure matters, counterparty quality matters and regulatory clarity matters. Ignoring these things is how operators end up with impressive demos and broken businesses, but understanding them is how you build something durable.

In other words: the market doesn’t care how fast your chain settles if the local currency on the other side has no buyers.

The next wave of stablecoin adoption will not be about faster networks or new chains. It will be about solving the second tail: creating predictable settlement in places where unpredictability is the norm.

The companies that succeed will not be the ones that talk the loudest about decentralization or speed. They’ll be the ones with quiet operational discipline, better corridor data, and a clear understanding of where the actual friction lives.

This is where stablecoin FX becomes real. Not in the first tail (the part everyone sees) but in the second one, where most of the real work happens.