Should all intelligence agencies be required to share all information and intelligence they gather with all other agencies? Why?

There can be many different kind of intelligence agencies
within a a country as well as across the national borders. For example there may be
intelligence agencies dealing with law and order, national difference,  industry and
business, and economic conditions. It is neither practical nor necessary for all the
information gathered by all such agencies to be shared by them. Also, in sharing of some
type of information may not be in the interest of the purpose for which the information
is gathered. The simplest example of this is the information gathered by companies. The
competitive advantage of having such information will be lost, if such information
becomes a common knowledge.

Also there is the need for
keeping some kind of information confidential or secret. In all such matters it is a
good principle to release the information only to people who actually need to act on the
information.

Also we must consider the fact that too much
of information can also be as harmful as not having enough information. A person who
receives 10,000 pages of information cannot possibly uses all the information available.
As a matter of fact the person may need to spend so much time and effort to sort out the
useful information from the other information, that he or she will have very little time
or energy left to actually act on the information.