Running for running

Why don't we get pregnant even when we track ovulation and baby dance on all the right days? - baby ovulation

I do not understand. Including me and many other women here try baby monitor their ovulation and dance like crazy in order to get pregnant without success. So Aunt Flo rears its ugly head after 2 weeks. If they are found millions of sperm and only one egg (perhaps 2 or more), so why not do the job? CFR