[dukwon]

> Do they not show up in all collisions

This is the biggest factor

> why not, wrong matter, wrong speed?

Quantum mechanics is probabilistic. The probability of these particular particles in these particular collisions is very small. So we need to do a lot of collisions in order to have a statistically significant signal.

> but the "camera" has limitations?

Sure. While we regularly upgrade our detectors or build newer, fancier ones, there will always be some limitations.

> but measurement interpretation inefficient?

It's certainly slow. It can take months/years to infer a result from the data. The major bottleneck is people. Even the thousands-strong armies of physicists who work on the LHC experiments would take decades to fully exploit the available datasets.