Hi, why do women join dating sites and then when contacted do not reply? Even a nice NO would be apreciated.

I agree with what you say, abuelo, it's happened to me many times. The word ignorance comes to mind.

Hi Abuelo.

It has been said many times: No response is a response.

Also take into consideration the last time the person had been on the site. Was it recently? A week ago? A month ago?

Acknowledging emails with a polite 'Not Interested' can open a door for unwanted communication: Angry retorts, insults, etc.

One word emails of 'Hi' do not grab the attention of the receiver. Shows zero effort.

In a nut shell, some women find it not worth their time and energy.

Just move on.

Best Wishes.

Not really a reply.