Complete career changes in general can set your advancement back quite a bit. However, they can also be the one key thing that will get you moving and get you out of a job and career that does not offer any further possibilities for yourself to grow and advance on your career. Well planned and executed career change with synergies between old and new careers can expand your expertise and can catapult you on a fast track to success after years of stagnation. These linked career changes offer some unique opportunities, if you manage them so that your previous career supports your new career, and in best case, gives you an additional deep knowledge or a skill set that the people at your new field usually don’t have.
For example, a career move from manufacturing industry to software industry for an engineer who was also managing some manufacturing related software can provide some very good synergies. It is a complete change of industries, but the expertise from the old industry will give the engineer an excellent perspective and hands-on knowledge of the manufacturing industry, which can help tremendously when for example designing solutions for manufacturing companies. This kind of deep hands-on expertise will be very much appreciated in the new company, as it gives them a much better understanding of the target industry they are serving and building products for. The customers will be also able to communicate their needs much better with someone who has first-hand experience and understanding of their industry and its processes.
My advice is that you will look for a complete career switch only if you are absolutely stuck on your career, or don’t have any passion for it anymore. It will most likely set you a bit back, but if you have been stuck in your previous career, it is better to take a lateral move, or even a fall back move to a new industry and lower level job to end the stagnation and get moving again. If you come to the conclusion that a career switch is necessary for you, then look for all the possibilities where your old career would bring in synergies and gives you the biggest possible advantage on your new career on your chosen industry.