5 stages

There are 5 stages to learning any form:

1. The pattern
2. Internal strength
3. Application
4. Shen
5. Natural

With the advent of tai chi sport forms emanating from modern China, many modern practitioners never proceed past stage 1.
Indeed, few people even realise that there is more to form than the outward show.

The sad part about this is that the pattern is essentially incorrect unless augmented by the other 4 stages.