Always drive within your competence, at a speed which is appropriate to the circumstances so that you can stop safely in the distance that you can see to be clear.
In driving, as in life.
This advice really only applies in contexts where the risks of failure substantially outweigh the rewards of success. This isn't true in many contexts; if they're approximately equally balanced, it makes sense to attempt to work slightly above your level of competence in order to improve your skill, and if the rewards of success substantially outweigh the risks of failure it makes sense to be even more risk-loving.
First-time poster, long time lurker. This discussion piqued my interest.
If you have your own business, a very cost effective way of promoting it is to get a part-time job, (or 'side quest' in D&D parlance) that involves delivering something such as catalogues, phone-books or even takeaway food or a paper-round in the location where your business operates. You can easily slip in your own flyers or business cards in along with whatever you are delivering. The wage from the part-time job will easily pay for the extra printing and mileage costs. I do this ...
I think that you may have misunderstood the point that I was trying to make. I am not advocating excessive caution. Rather, I value self-knowledge and knowledge of the environment and the people you interact with in that environment. Obviously, a certain amount of margin of error should be included in any decision making.
It has been my experience as a driving instructor that most pupils are entirely too cautious especially on faster roads where going too slowly may cause a following vehicle to attempt an unsafe overtaking manoeuvre