The errors are correlated, not random. Lumps are usually benign cysts. If you start cutting people open for every cyst on a scan, you’d kill a lot more people than you’d save.

This isn’t something you can solve with more scans because the tests test for data that is indistinguishable. They look the same on a scan, there’s an overlap in the assay with some random protein with the same binding sites that is only present in 1% of the population, the coding gene in one person gets repeated in a noncoding region in another, and so on. The “more data” that works is a doctor applying professional judgement (which they’re also famously bad at because biology is a fickle mistress).

More data (daily scans) can mean we get better at medicine, though, and more accurate. You're assuming "daily cancer scans" look just like they do today, rather than eg unobtrusive devices in our daily lives that measure changes over time.

The frequent "muh false positives" comment we hear from doctors appears to be a lack of imagination?