why we need to improve a process? the main reason is to increase the quality of the output. but in a case where the quality of the output is decreasing with the improvement of the process, is it worth to stick with the decision? of course not. you will spend lot of cost for something that doesn't bring benefit. in a way, you have to take a u-turn and go back to the old method. there is nothing u lost when you try the new method. even the quality doesn't increase, at least you know what is the wrong method so you will not repeat it again in the future.