Why would my partner be lying to me?

My partner has lied to me a few times about being on his way home from work when I know he is already at home. I have (wrongly I know) tracked it a few times and most of the time he is where he says he is, it’s only been a few work days where he has said he’s ‘ten minutes away’ and when I’ve checked he’s already been home. Could he be cheating?