I highly recommend that book "Mindset - Changing the way to Think to Fulfil Your Potential" by Carol Dweck.
There are two types of people, and when you read the book, you will spot them.
Growth Mindset is where people are always seeking new experiences and new learnings. There are also keen to learn new things.
Where as a "fixed mindset" sees everything as "shit". Fixed mindset people see the responsibility for things to be that of other people.
If you were in a job and you could sell, that would be the fault of the company and it's products and services. That wouldn't be your fault.
In fact Microsoft say that the fixed mindset vs growth mindset as to why they have grown as a business. People accepting change, people accepting new things, people accepting new ways vs the people that won't try new things.
Other fixed mindset symptoms are people who keep things to themselves rather than sharing. People that won't accept new things and just say they are shit. (Cold calling gurus are a good example of this!) People with a "not invented here attitude" are all fixed mindset.
The research I did at Oracle on high achieving sales people, the research that Microsoft has done on high achieving sales people all points to a growth mindset.
So what can you do?
Accept that you may not be right all the time!
Accept people have other opinions to you!
Accept and congratulation people when they come up with good ideas.
Say "I'm interested in your feedback, as I might learn something".
Go on training, again you might learn something.
Don't assume that everybody else is a fault, if there is a problem, look into yourself first before blaming others.
With maturity of any b2b business comes a need for its sales field to change and grow; to adapt to increasingly complex conversations that demonstrate a heightened relevance to the customer’s business, and which speak to the personal agendas driving individual decisions. They need to ascend the relationship chain in the customer and widen ‘known circles’, creating more senior relationships from scratch. In doing so, they can’t neglect existing relationships which risk creating a vacuum for competitors to exploit. And, they have to do all this whilst overcoming legacy perceptions about the limitations of the solutions they’re selling, which are constantly evolving.