Tnx for support.
Here's a simple explanation of how the two are different.
Let's say your car is stationary and the wheel is centered, you are not touching it at all. Then, from the side comes another car at a moderate speed that hits your car. Physics does its magic, calculates all the forces, and sends the FFB to a wheel. The resolution of that FFB signal has nothing to do with the game controller, it's inherent to LFS physics. Now, what the FFB wheel will do with that signal is another thing and it is very important for a final FFB feel. In the same way, you would hear a better sound with better and more powerful speakers. The song is the same, but what you hear in the end depends on the device you listen to.
Now, let's say FFB is set to 0. You drive a car around, there the resolution of the steering axis dictates what will be the minimal input you can give that the game can still sense and act upon. LFS can still send the full res of FFB even if the steering axis is very low res. But we talk here about how sensitive the car is to the steering input. It may be ok for a GTi car to have 2000 steps, but something more serious like a BF1 or similar will benefit from utilizing the full available res of the controller (16bit usually for wheel, 8 or 10bit for gamepads).
FFB consists of many effects (forces), some are dependent on the steering input, some not. For example, track shape and all imperfections get picked up by a tire and suspension system, and that causes some forces to act on a steering column and a steering wheel. Whether you move it or not, they're gonna be there as long as the car is moving.