A lawyer has to produce a draft of a brief or of a contract in time to meet a deadline set by the client's schedule, so the work output just has to get done. But the draft brief or draft contract works best to meet the client's needs if it is developed after thought, and being just-plain-busy isn't the same as thinking.
Right, but this goes back to a point higher up in this thread.
If Lawyer A writes the contract from scratch every time and takes two days, but Lawyer B has a modular contract-assembly system she optimised earlier and just needs to make a few tweaks -- which will take two hours -- which lawyer will you pick?
That human nature thing again: we'd distrust the person who can get it done too quickly. (Though, we might be able to grok the situation enough to appreciate B's initiative and, especially if we wanted a lot of contracts, might be able to override our instinctive reaction that she hasn't had enough time to think about it properly.)