In a Mises wire, Daniel Lacalle explains May's Way Is Not The Only Way.
In a nutshell, May's Brexit is the worst solution for Leavers and Remainders. It tries to please Remainders, who are obviously not satisfied as they want a full reversal of the EU exit.
In essence, the plan is the worst of both worlds. Leaves the UK with all the perceived negatives that led to a "Yes" vote in the referendum and none of the alleged benefits of staying in the European Union.
May's way is not the only way. The UK should deliver a strong Brexit proposal that creates certainty, that eliminates the excessive costs and regulations. There is a reason why the EU has a "Canadian" or "Norwegian" solution because they were created ad-hoc for those countries. May fails to recognize the strengths of the UK to achieve a specific "British solution" that is good for both parties. She seems to accept at face value that the EU rules, those that the EU itself bends at will, are untouchable.