Mistakes happen all the time in Project Management, however don't fall trap to one of these common mistakes that could be avoided:
Under communication with team members and not being effective in your communication is one of the biggest mistakes PMs can make.
Projects suffer from ineffective communication, whether that be not communicating clearly, or being in a hurry and missing key details.
In projects that are failing, there tends to be a rush in communication and not enough time spent planning out communication, which is putting the project even more at risk.
2) Too Much Structure
We as project managers love planning and project management tools and techniques, so it's easy to place too much structure for our teams in an effort to plan.
It can make it difficult for your team to be efficient and effective when they are trying to work within a rigid structure.
Knowing how much structure, especially around the planning element, to put into a project is important.
3) Not Being In Person / On-Site
Obviously virtual teams can't be on-site, since there isn't one. Communication takes place online, through computers, phones, emails, etc. However, in other projects where you are at least in the same city if not in the same building, project managers need to be visible, Attending meetings, observing team members, getting face-to-face and in person dialogue is critical for effectively managing a project and more importantly your team. A lot of project managers tend to get caught behind the screen and that's where they stay, relying on computers and telephones to manage their teams.
It's extremely important, if possible, to connect offline with your team. This allows project managers to gather information about their team members, where the project is at and truly best manage resources. There are too many things missed if not at meetings in person.
4) Being In-Personable
Not being approachable is a huge mistake in project management. You need to be able to have an open door, where your team members feel comfortable to approach you with any issues or questions that might arise during a project lifecycle.
Project managers also need to have an open mind. Certain techniques might not work from one project to the next so it is important to be flexible and open to change.
5) Too Much Focus On Tools
Similar to point #2, it can be easy to bury yourself behind a project plan. The project plan is a tool, not a replacement for discussoins, conversations and dialouge about the project.
The proejct plan is there to help and assist, not to act as the project manager. Project Managers need to gleam real-time information from their team to make the best decision for the project.
6) Being Realistic
This point falls more on the organization. A lot of organizations have unrealistic goals and expectations of a project, especially around scope, schedule and budget.
It is important for the organization to understand that only so much can be done given resources, budget and scope of a proejct. We can't create an extra hour each day, turning 24 hours into 25. We also can't effectively execute a project with only 4 resources when really it really needs 8.
Project Managers are faced with unrealistic expectations from leadership all the time, even when requesting more scope, resources or budget. It is important to keep in mind that your job as a PM is to keep an open line of communication with leadership about these expectations versus the reality of the project.