Sometimes the info blackout is warranted. Certain surveillance operations can be compromised if too many people know what’s going on. In other cases, you may be working on an operation where there are already sufficient personnel involved and enough time and resources allocated to ensure that it will be a success. And of course, you could have the suspect in a contained environment wherein his seizure is virtually inevitable. These are all good reasons not to worry about sharing information with fellow officer or even to avoid doing so.
But in the majority of situations keeping information to a select few can be selfish and even dangerous.
Consider, for example, surveillance operations that do not run 24/7, where suspects are occasionally at liberty to be detained by patrol officers who may not know what they're in for once they pull such suspects over, or otherwise detain them. At these times it’s best to share the info.
It’s also a good idea to share recently acquired street intel on the last known locations of wanted gang members, or previously unknown locations where they hang out, or what G-ride they're tooling around in. If a parolee at large just happens to have been hanging out at a local watering hole, woe be unto the officer who picks an inopportune time to do a bar check. And woe unto the cop who withheld the information that might have helped him.
Selfish rationalizations for keeping information in house include: It's my collar, my informant, my work, etc. The other guys don't want/need/deserve to know, and wouldn't do anything with the info anyway (a contradictory notion given the foregoing concern). But the bottom line is that it is often the result or selfishness and arrogance.