I've entered all the routes I've taken that I can remember, but not all the individual flights.
I got tired when I started entering all the Bay Area to L.A. area flights. I've flown that route several times a year for the last twenty years. There's no way I can even remember exactly how many times I've flown that route, let alone have the patience to enter them all. So I gave up.
So the total mileage of my flights is wrong, but the maps are correct.
Ed