Answer to Question 1
If you present a totally new business concept, it's possible that the market won't be able to compare you to your competition, which means your product won't be considered as part of the market or you may lose market share altogether. The lesson is that you want to be different but not too different.
Answer to Question 2
The two arguments are equally flawed. If driving slower is going to save you money on fuel and will reduce your likelihood of having an accident you should drive slower. The same is true of tariff reduction. If reducing tariffs makes your country better off then it doesn't matter whether your trading partners follow your lead. You should cut tariffs anyway.