So there has been a lot of talk and speculation about the apple watch not having enough battery (2-5 days)....Here is my argument..... Firstly I believe that either the watch should have a 20-24 hour battery life or a 5 day battery life, anything in the middle doesnt cut it. This has been apples philosophy with the iphones too. I own a nike fuel band and that lasts 5 days on a single charge so I remember to charge it on a weekly basis. If the apple watch had a 2day battery life then it will be very hard for people to remember when to charge it and when not to. This will be a major inconvenience for a lot of customers coz individual mileage varies and having a watch run for more than a day is going to leave a lot of people with blank screens in the middle of the day (you can imagine many scenarios). Rather its better to charge it every night coz people are already in the habit of charging at least one gadget every night. Apple uses the 90-90 rule ( what 90% customers use 90% of the time) so we are unfortunately left out but thats the case with iphones too. My iphone can barely get me through a day but for 90%of the people it does. Apple knows that there is no point in giving the iphone a battery that lasts more than a day. Charging any device every 2 days just doesnt make sense from an average customers point of view. So I believe that currently apple is trying to nail that 16-20hr heavy usage scenario and nothing more than that coz 5 day battery life is impossible with current limitations in technology. So we just have to bite the pill and accept it.