Use my remote location for internet on specific VLAN - Wireguard

RouterOS Beginner Basics
9

CGGANNX why is

add action=lookup-only-in-table dst-address=0.0.0.0/0 interface=VLAN21 table=wg-route-table

preferred over

add action=lookup-only-in-table  src-address=vlansubnet  table=wg-route-table