I sometimes am the one who decides there is no chemistry and ends things. I'm in therapy so I can ask my therapist what she thinks I'm doing wrong. Personally I just think I'm not flirty enough, I don't really know how to flirt aside from giving compliments or saying sweet things.
I disagree that letting her know I got home sounds lame and weak. I think it's a sweet gesture. And like I said, she asked me to tell her when I got home. For some reason, women get home and their opinion changes of me. They like me while on the date, then they get home and can think about things and are like "hmm I don't actually like this guy." After she ended things with me, I did ask her what she didn't like and she couldn't name anything specifically and just said she didn't feel chemistry.