Flexibility VS. Mobility
Flexibility and mobility. Although similar terms, there is a difference in what does vs the other. I use the term vs because although sometimes they can close like brothers and help each other out, they can also be related like brothers and impede the other from doing its job. For example I can have great hamstring flexibility but poor hip joint mobility which will affect the hip functionality. If you can touch your toes with straight legs, then that is an example of great hamstring flexibility. However, if you can't squat to 90 degrees (or slightly above or below), or if you can't do a hurdle step (normally a dynamic warm up drill. Find reference on YouTube) then that is a sign of poor hip mobility. So, poor mobility can directly affect flexibiltity in the same region or somewhere else in you kenetic chain. I would suggest implementing both mobility and dynamic and static drills/stretches before, during and after your workout (you don't have to include in all moments, this is just a suggestion). By doing this you will take out the VS and replace it with a more harmonious term like &. The ideal scenario is to have both. If you are able to achieve both of these then you will see great performance gains.
Have fun, stay fit, move athletic. Ryan