Closely guarded (reserved) executives

Everyone is fighting with the next person for something. Even the people working in the same team are fighting for the promotion or getting some sort of rewards. In some of the industries it is very important to have close team work but all the members are competing with each other. How can they be good team members?
Most of the senior executives are very reserve when it comes to communicating with the new people. They speak some very diplomatic things and one cannot make any sense of what they are trying to convey. This is because of their experience of working with different teams and people. Whenever someone opens his/her mouth other people start interpreting something for their benefits.
In today’s fast communication it is very tricky thing to use email system. Anyone can do CC or BCC while replying or writing an email and it puts the recipient in little dilemma. If you don’t want to reply some email, people will put your boss in CC and then you have to reply. Even if you find out problem in others work, they might find other ways to defend themselves by using polished language and you may find yourselves in messy situation.
Because of these reasons, senior executives prefer not to speak much with new people. But this is caused problem even for them. For example, when they hire consultants to solve some issues, they are so reserves that consultants find it difficult to get information. In this situation, how someone can help when the client is not willing to share information.
Consultants first need to build trust and credibility to win the trust as soon as possible so that they get real information to proceed further.