It it’s starting to become difficult to turn your Volkswagen or Ford ignition barrel then don’t ignore it. Get it replaced ASAP. WD40 isn’t going to repair worn metal or a broken spring.
Ford Transit and Custom ignition barrels are well known for failing. You might be able to wiggle the key and get it working today, tomorrow it might jam forever and you’ll be stuck at the side of the road. It is easy to replace when you can still turn the key. It’s a lot more difficult to replace when the lock cannot be turned.
VW, Audi, Seat locks tend to fail in a different way. It isn’t the lock barrel that fails. It’s normally the steering column housing. Again, don’t ignore it. To repair it may require cowling off, airbag off, steering wheel off, switchgear off. (If the steering wheel etc have to come off then that’s a job for a mechanic).