Being informal is not a bad idea. Being hundred percent informal may break your business into pieces. Building a business requires to gather hundreds of bits and pieces. It takes sweat and build and unknowingly you break it when you are hundred percent informal.
Being too much informal is sound rigid even if you don't mean then too a client, a customer, a support staff may consider you dominating or arrogant. Building a business requires partnerships not one but many.
The legendary cricketer Sir SR Tendulkar has mentioned in many interviews, 'cricket is about partnerships and its not only cricket, life is about partnerships.'
Being realistic is fine but being too realistic can break that partnership that you have built over years. Relationship building is a task. And just for one small reason which may even be not reason you can break a beautiful partnership with a potential prospect.
People in and around me are often happy in my company. Together we enjoy pretty good time. But at times a felt a good partnership has broken because I turned too realistic.
This does not mean you should lie or promise for a thing that you actually cannot provide.
Sometime you need to do task, or say yes, ok for something that you actually not enjoy from within just make other person feel happy. When people offer you something or expect something from you because they feel they are important to you.
And you turn out too much straight forward, even your partners know, you do not mean to insult them, but somewhere in within they feel insulted. It does not a fraction of a second to make someone guilty but it takes whole lots of efforts to build those bonds.
If you are not bonding well you are not branding either.
Even if one person is unhappy who associates with you then its your mistake. No mistake is large enough to carry as a burden and no mistake is small enough to ignore. Correct it now.