What are some disadvantages of a new business entering the market?

What are some disadvantages of a new business entering the market?
Political situation is unpredictable. Your business must assume what the market will be like but political decisions change the market overnight. I had to close my business twice because it depended on contract work. the UK government suddenly decided to squeeze credit and businesses stopped using contractors suddenly leaving me with no inclome. The Eurozone is going to collapse unless their difficulty in balancing payments is fixed and there is no sign of that happening. The US also has borrowed Trillions and is overspending so that could have a crisis as well. So unless you can run the business without bank credit and close it down quicly I dont advise starting one now.