Using all of the available lane while entering the corner (square line) provides a number of benefits. It allows you to brake while upright, see farther through the corner and use later corner apex, you can get on the throttle earlier as you stand the bike up out of the corner. The low entrance line (dotted line) forces you to lean over even after the apex and is a major contributing factor to overshooting a corner, always give the centerline some room; stay right except to pass.