Many of your own errors will be due to rushing. Others will be down to inexperience or a lack of particular skills.
The latter can be corrected by suitable training programmes.
If you are rushing jobs this may be due to a genuine lack of time for those tasks that have just appeared or more likely due to poor organisation skills.
Make sure that you are happy at the ranking of your tasks and you spend the appropriate amount of time on ‘important tasks’ and do not allow any planning of tasks to weaken your time spent on Box 3 items, see ‘urgent v important’.
You may be unsure of your own errors and why they occur. If so, keep a record of problems and their causes and how frequently they occur.
Armed with this information you can put into place adequate solutions. These could be training as above or improving your use of the time available.
Many tasks often have common elements to them. For example, if you travel a lot to the same place you will order taxis, pack suitcases, take money, travel with particular files, perhaps a laptop with CD’s etc. Don’t reinvent the wheel by sorting out these items each time. This act can lead to urgency and rushing. Maintain lists of these common items and use them each time you need them.