It's probably not really laziness (or maybe it is? lol) but maybe she doesn't like the feeling of the harness or something makes her not want to go forward. You say she doesn't usually go for walks? She's probably not used to someone controlling where she walks and goes and she doesn't like it, so she's being stubborn.
I would try to lure her forward by holding a treat in front of her as you walk and see if that works. Reward her whenever she walks forward. |