According to Wikipedia:
Reuse is the action or practice of using something again, whether for its original purpose (conventional reuse) or to fulfil a different function (creative reuse or repurposing).
When we are developing a new feature it is quite common that we implement some parts of the code in way that it can be reusable. It is a trap, don’t do it. To reuse something, you first have to use. Use your code in production, than evolve it to be reusable if you have to.