The internal arts teach the student to move the entire body towards the opponent, rather than stretch out the limbs.
Stretching is regarded as foolish:

1. It exposes the ribcage, armpit and torso
2. It makes the joints less resilient
3. It makes it easier for your balance to be taken
4. An opponent can avoid a strike more easily
5. The further out from the centre you reach, the less power you have

Rather than stretch, you step.

If you cannot employ optimal power at your current range, do something else.