Why Your AI Demo Works — and Production Doesn't
Every vibe coder has lived this: the AI builds something, you click through it, everything works, you share it — and it falls over the moment someone else touches it. The gap between "worked in the demo" and "works in production" isn't bad luck. Demos hide specific things, and the same ones show up again and again.
The demo data was doing the heavy lifting
Generated apps usually arrive pre-seeded with tidy example content — three well-formed cards, a five-star review, a user named Alex. Real data is nothing like that: empty lists, missing fields, a name with an apostrophe, a 4,000-character comment. The demo never exercised any of it.
Surface it: delete the seed data and use the app cold. Then feed it ugly input on purpose — empty, enormous, malformed.
Only the happy path exists
Unless asked, models generate the success case: the request succeeds, the field is filled, the file exists. The demo clicks straight down that path. Users wander off it immediately — they double-submit forms, lose connectivity, refresh mid-save, and paste emoji into date fields.
Surface it: for each action, ask "what happens if this fails or happens twice?" — then make it fail and watch.
The data never left your browser
A very common pattern in AI-built apps: persistence via localStorage. It looks like a working database in a demo — but the data lives only in that one browser on that one machine. The moment a second person opens the app, they see none of it, and nothing is shared between visitors at all.
Surface it: open the app in a different browser or an incognito window. If everything's gone, your "database" is per-device, and shipping it means every user gets a private, vanishing copy.
It only ran on your machine, your screen, your network
Hardcoded localhost URLs, layouts tested at one window size, and instant local responses all pass the demo. Production means other devices, small screens, and slow networks.
Surface it: test at phone width, throttle the network, and search the code for "localhost" before deploying.
Placeholders passed as content
Demo eyes skim past [PRODUCT_NAME], lorem ipsum, and dead "#" links. Users don't. A working-looking page full of placeholder fragments reads as broken — because it is.
The mindset
A demo is the app on its best behavior. Production is the app on its worst. The fix isn't cynicism — it's a short, deliberate pass where you play the role of the distracted, offline, apostrophe-named user. Everything you catch there is a bug report you'll never receive.