13 resources from Andreessen Horowitz we point founders to, and the questions each answers.
✍️ Essay
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Why we picked it
When there is no category report to point at, you have to build the number yourself, and this is the essay that teaches you how. It walks through bottoms-up sizing (start from your actual customer, their willingness to pay, and how you will reach them) and shows why the top-down 'we just need 1 percent of a huge market' story falls apart. Treat it as the method for a defensible estimate, not a promise about how big you will get.
From
Andreessen Horowitzby Anu Hariharan, Frank Chen, Jeff Jordan~20 min read
Build TAM from the bottom up: real customer profile times realistic price times how many you can actually reach and sell to.
Top-down percentages inflate the number and hide the hard part, which is distribution and go to market.
Some of the best companies (eBay, Airbnb) started against a market that looked small, then expanded the use case, so a modest starting number is not a dealbreaker.
Why we picked it
Early sales is not about volume, it is about finding the few customers who want your vision badly enough to bet on an unproven product. This piece explains why the founder is the most effective salesperson at the start and what that selling actually looks like. It also names the trap of staying founder-led too long, so you know what you are aiming at and when it changes.
Why we picked it
This explains why niches once dismissed as too small (laundromats, vets, clinics) become real businesses when AI absorbs the labor-heavy steps and drops acquisition cost. That is the economics shift at the center of your question, shown concretely. Use it to see how a specific painful job in a small market turns into an opportunity.
Why we picked it
The core move in our short answer is decomposing a workflow into steps a model can now do. This piece frames every workflow as a vertical AI company waiting to be built, and shows where agents can take over multi-step jobs. Read it to practice breaking a real job into the steps you would hand to software.
Why we picked it
The opportunity is often a capability that already works in a raw model but nobody has wrapped into a specific job yet. This piece is about exactly that gap between what AI can do and what has been turned into a product. It helps you spot where good-enough automation exists but the painful job around it is still done by hand.
Why we picked it
The same argument as the essay, but spoken, if you would rather watch than read. Dixon walks through real markets that looked tiny and then compounded into the main event. Good to send a co-founder or investor who doubts your small starting point.
Why we picked it
A short primer on how real technologies move from ignored to inevitable in an S shaped curve, and why early flatness fools people into calling something a fad. It gives you a picture for where a trend sits on its curve, so you can ask if adoption is about to inflect or has already peaked. Helpful vocabulary for judging durability.
Why we picked it
Andreessen's 2011 essay is a masterclass in spotting a durable secular shift early and betting on it before it is obvious to everyone. It models the kind of why now reasoning your question needs, naming the trend that quietly reorders an industry. Read it as a template for arguing that a moment has genuinely arrived.
Why we picked it
Horowitz explains why founders hold a knowledge advantage no hired CEO can replicate, built from every early decision, hire, and piece of customer feedback. It is the clearest case for why 'why you' compounds over a company's whole life. Useful for articulating the durable edge you carry as the founder.
Why we picked it
A compact roundup of Dixon's startup thinking, including founder/market fit and why passion for a problem beats chasing a hot space. It is a quick way to internalize how a top investor weighs the founder behind the idea. Good as a primer before the deeper reading.
Why we picked it
The clearest explainer of how VCs actually decide, from term sheets to how partnerships evaluate founders. Understanding the machine is leverage when you cannot rely on informal signaling to carry you. Read it so you play the funding game knowing the rules, not guessing them.
Why we picked it
Each year a16z partners publish the problems they think startups will tackle next, which is less a prediction and more a map of where serious money and attention are about to flow. Reading it shows you what a room of full time trend watchers is paying attention to. Treat it as a prompt to argue with, not as gospel.
Why we picked it
A concrete worked example of AI aimed at a famously boring niche, accounting, rather than at a flashy consumer app. It shows how a hot enabler unlocks a fragmented, underserved market that generalists ignore. Use it as a template for how to think about your own boring-niche-plus-AI opportunity.