What this leads to is them cutting and pasting an identical message to send to each one. It also means that they have checked out her photos - and spent 1 minute at most checking out her profile. What they read in the profile they immediately forgot, or was irrelevant to the message they sent to her.
The result - 95% of communications that go nowhere. Taking a sales analogy here - at that rate of converting leads that would get you fired from any sales job INSTANTLY.
Getting results from playing the numbers game online is a MYTH.
You need to focus on a maximum of 4 or 5 communications with women per session (and that's considering a couple of hours time investment).
Find out who she really is, and send her a personalized message that will make you stand out from the 'spam fest' attacking the best women's inboxes. Read her profile. Understand it. Think about who she is. Communicate to that.