Most people who ride bicycles for pleasure do not ride until the warm weather of spring and summery arrives. Yet it is probably more effective to advertise bicycles earlier in the year. Most bicycles are purchased in the spring, but once shoppers are ready to shop for a bicycle, they usually have already decided which brand and model of bicycle they will purchase. By then it is generally too late to induce them to change their minds. The main point of the argument is that ['bicycle advertisements are probably more effective if they appear before the arrival of warm spring weather', 'most bicycle purchasers decide on the brand and model of bicycle that they will buy before beginning to shop for a bicycle', 'in general, once a bicycle purchaser has decided which bicycle he or she intends to purchase, it is difficult to bring about a change in that decision', 'spring and summer are the time of year in which bicycle riding as a leisure activity is most popular']