1) What the company does and how well is it doing?You should know the company's business and track its performance.Who are its competitors and how are they faring?
2)How the stock price behave in the past? You should track the stock price history.Find out when the investors found it the best or worst time to buy and sell the stocks in the past.
3)How will it behave in the future?The future is not ours to see but then it pays to make an estimation of what price the people will pay for the stock.
4)How good is the stock compared to others?The comparing helps to make the best purchase. Weigh the stock against any other be it from another sector.
5)Are you missing out on any other vital information?You should catch on the recent information about the company.Do the broker's find the stock attractive?