Yes, the springs are supposed to keep the valve centered in a neutral position.
When the springs are correct, there is equal force on the spool, keeping it centered.
In neutral, the flow in an open center hyd system is flowing through all valves to tank.
If the valve spool is not centered, the fluid is being directed to somewhere and if you are talking remotes, the fluid is going to whatever is plugged into the remotes. If it is a cyl, it will move, and if a hyd motor, it will turn.
It is easy enough to tell if the fluid is flowing through a work port, If you remove the hoses on the remote valve work ports, and start the engine, fluid should flow out one of the work ports if the spool is not in the neutral position.
In the normal mode, with all valve levers in neutral, no fluid should flow from the work ports. Here is an example of centering springs on a spool.
First picture is a
B3200 loader valve.
Items C and M are centering springs.
Second valve is from a Case skidsteer items 5 and 12. Centering springs are a common thing in hyd valves. You will also notice the nut or screw holding the springs tight and set correctly.