After the " Fly 3.0 " series in 2015 , we planned to make one series of waterproof shoes . To keep the shoes design of " Fly 3.0 " series , we used the shoelaces as usual , change it to more breathable net cloth for the inner sole , chose LYCRA on outside to make it sounds like so fun so good . In fact , we found so much problem when it starts to have a high volume of production .
Problem 1 : the material for outside is too soft , even can not to reinforce .
Problem 2 : The good walking experience was governed by the structure of the shoelaces on heel .
Problem 3 : As a result of the outsole is too shin and without any reinforcement , when put it on , that was not a thing can be called "shoes" , just a kind of combination .
Also because the style of shoelaces , you will feel it is too tight on at the ankles , that is the reason why the shoes make people feel uncomfortable .
As a result , The first prototype became one of thing that only can be watch without any practical value......