can I prevent a thief to use my watch

for the moment my Watch is not stolen, the device is paired with my iPhone.

I want to know whether a problem might occur when someday the watch is stolen.

the watch will unlock when the iPhone is unlocked, whatever reasen.

is it possible the thief is waiting nearby till I unlock my iPhone and so unlock the watch also.

of coarse the thief shoulw wearing the watch his wrist.

once unlocked he can use it to make payments.

and because I want to know if that is possible, I have NOT activated payment by watch yet.

Thank you.

still I have two other remarks:

1. according the watch app at my phone the watch will be unlocked (when set to do) by unlocking the iPhone.

I have noticed this is not true, my watch is unlocked when my phone is unlocked.

2 the watch is unlocked by the iPhone at 5 m distance.

perhaps it is better to decrease this distance to p.e. 20 cm.

or to unlock when both watch and iPhone make the same movements (phone in hand, watch at wrist).