We might never think about it, but really there are so many tznius pitfalls in dating. In the car alone. Walking at night alone with an unrelated girl. Talking alone, away from everyone, with an unrelated girl about sensitive and frivolous subjects.
Sure we can justify all this as being for tachlis. And of course there are heteirim to be found. But really our zeidas or elter-zeidas or elter-elter-zeidas, for those of us lucky enough to have an all frum yichus going all the way back to Avrohom Avinu, didn't date. For thousands of years our zeidas father would work out a shidduch with the girl's father and mazal tov! The boy and girl would briefly meet in a beshow type of meeting, and if there were no objections agree to get married, vzeh hu.
And we know that even today there are alternatives to the problems of dating. Hundreds of thousands of Yidden around the world got married without dating. They had a beshow, all in the tzniusdik confines of the parents home, and are married. The concept of frum Yidden dating isn't much more than a hundred years old. And for most frum Yidden it started much more recent than even that.