When Bad Assumptions Blow Up Your Budget (And Your Business)

We had a great conversation this week with Dr. Adam Link — yes, he's a real doctor, no he cannot prescribe you anything, and yes he somehow went from finance to software engineering back to finance. The man contains multitudes.

Adam's now a CFP running Firewood Capital, and he came on to talk about something that hits close to home for anyone who's ever managed a process, a codebase, or a retirement account: bad assumptions compound over time, and eventually they blow up in your face.

Testing in Production

Adam dropped one of the best lines early: in software, you write code, test it, and if the output is right, you move on. In life? You're testing in production. There's no sandbox. There's no rollback.

The financial version of a production incident is realizing at 55 that you never contributed to your 401k. You can't go back to being 21. The bug has been in the system for 30 years, and now you're dealing with the consequences in real time.

That's not a fun conversation to have with a client. It's a much better conversation when you catch it early.

Compound Interest Is Genuinely Magic (Sorry, Had to Say It)

Look, everyone's heard this. But Adam put it in terms that actually land: $10 on $100 isn't impressive. Ten percent on $100 million is $10 million a year — a million dollars a month. The math doesn't change, the base does.

Start small, stay consistent, let the base grow. That's it. That's the whole thing. The boring moves are the right moves.

Case in point: Adam recommends auto-escalating your retirement contributions by 1–3% every year, roughly in line with inflation. You get a raise, your contribution ticks up, you barely notice. Meanwhile, future you is doing great.

The 100% Guaranteed Return You're Probably Leaving on the Table

Adam doesn't use the word "guaranteed" lightly — but if your employer matches your 401k contributions and you're not taking the full match, you are leaving a 100% return on the table. He knows of no investment that can promise that in a single year. Neither do we.

Take the match. Every time. Full stop.

Tech Debt and Process Debt Are the Same Problem

This is where it got fun. Adam made the case that tech debt and financial debt are basically the same concept in different costumes.

Taking on a little debt? Smart — you're growing faster than your current capacity allows. Taking on so much debt you can't make payments? That's when Amazon goes down and takes half the internet with it, or when a company is so buried in bugs they can't ship a single new feature.

The sweet spot exists. Zero debt in business — financial or technical — actually means you're moving too slow.

The Mental Accounting Problem (Silos in Your Budget)

Here's one that stings a little. Adam sees it all the time: someone carrying $10,000 in credit card debt while sitting on $20,000 in savings they've labeled their "emergency fund."

Mathematically, you pay down the debt. Obviously. But — and this is the part that matters — what if that savings account represents more financial security than your parents ever had? What if it's not a financial decision at all, it's an emotional one?

Optimizing one process at the expense of another isn't optimization. It's just moving the problem. Adam has to work with the whole system, not just the spreadsheet.

The Entrepreneur's Dilemma

Toby asked Adam something that doesn't get discussed enough: when you leave a corporate job to start something, you're giving up predictable income and a guaranteed return on your 401k match. How do you make that math work?

Adam's honest answer: it often doesn't, mathematically. Most entrepreneurs won't out-earn what they would have made staying put. But they're not optimizing for money — they're optimizing for autonomy, ownership, and the ability to say I built that.

The catch? When it comes time to sell the business, you're not just selling an asset. You're selling a child. And that emotional investment makes it genuinely hard to take even a strong offer. It's not irrational — it just means the financial decision and the emotional decision are the same decision, whether you like it or not.

If any of this resonates — or you want to find out what your actual retirement trajectory looks like right now — Adam runs a free first consultation for Process Debt listeners. You can find him at fireweedcapital.com or reach him directly at adam@fireweedcapital.com.