Originally Posted by
Worcester
Also bare in mind that randomness make it much harder for terrorists and criminals to get around security. If you simply don't know what you are up against, you can't figure out the risks or how to avoid them. Any good security system is going to make use of random selections for this reason.
The so-called random selection used for aviation security can be easily worked around, since the outcome of being randomly selected is easily enough known in advance of taking a trip when "randomly selected".
The POTUS' security detail, for example, doesn't rely truly upon randomness in security.
The UA SYD-California selection of jediwho isn't random, even as there is a percentage of passenger it purposely selects for "random" selection and associated "extra" "security".