Many of the people I train work alone or with a small group. They are professionals in practices, solopreneurs or entrepreneurs running small businesses. One of the reasons they value training is that they do not get to spend enough time collaborating to get to results that are one step beyond what they can imagine on their own.
Collaborating means working with people who share your purpose and frame: they are working within the same conditions to produce the same result. It also means working with people who do not share your expectations, limitations or special gifts. This mix of like-mindedness and variety allows a group of collaborators to produce more together than they could working alone. Sometimes more refers to quantity but most often it refers to the ability to generate innovations that no one person would have been able to create.
If you work alone or with a small group of people who are both like-minded and like you in gifts and limits, then you are not achieving as much as you could in a wider collaboration. There are different ways to address this so that your brain is sparked by ideas you would not have had on your own. One way is to work with a coach or trainer who can introduce difference into your thinking. Another is to work in a training group where you will encounter multiple perspectives and interact with multiple states of mind.
If you're spending too much time in your own work and not enough time being surprised by the work that is generated through a combination of difference and good will, then consider finding a training where different people come together for a short, intensive burst of speculation and innovation.