Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

Why is it important to research a stock before buying it?
Most markets around the world have been downtrending for the last 6 to 10 months. The definition of a downtrend is lower lows and lower highs, and until you get a higher low and confirmation with a higher high the downtrend will continue. If you look at the weekly charts of most indexes you can determine the longer term trend. If you are more concerned with the medium term trend then you could look at the daily charts. So if your objective is to try and buy individual stocks and try to make some medium to short term profits from them I would start by first looking at the daily charts of the index your stock belongs to. Only buy when the intermediate trend of the market is moving up (higher highs and higher lows).  You can do some brief analysis on the stocks your interested in buying, and two things I would add to the short list in your question would be to check if earnings are increasing year after year. The second thing to look at would be to check if the earnings yield is greater than the dividend yield, that way you know that dividends are being paid out from current earnings and not from previous earning or from borrowings. You could then check the daily charts of these individual stocks and make sure they are uptrending also. Buy uptrending stocks in an uptrending market. Before you buy anything write up a trading plan and develop your trading rules. For example if price breaks through the resistance line of a previous high you will buy at the open of the next day. Have your money management and risk management rules in place and stick to your plan. You can also do some backtesting or paper trading to check the validity of your strategy. A good book to read on money and risk management is - "Trade your way to Financial Freedom" by Van Tharp. Your aim should not be to get a winner on every trade but to let your winners run and keep your losses small.