Why do women discount and dismiss men who are eager to commit themselves right away?

1. Women understand the male role as the gatekeeper of commitment, just as we are the gatekeepers of sex.

In the same way that a man may question the long-term potential of a woman who grabs his junk on the first date, women are wary of men who are “emotionally promiscuous.”

Certain it is I liked her, 
And boarded her i’ the wanton way of youth: 
She knew her distance and did angle for me,
Madding my eagerness with her restraint, 
As all impediments in fancy’s course 
Are motives of more fancy; and, in fine, 
Her infinite cunning, with her modern grace, 
Subdued me to her rate: she got the ring;

Shakespeare, All’s Well That Ends Well

2. Some people are serial monogamists – the minute one relationship ends, they’re auditioning everyone in their sphere as a potential replacement.

A fellow SM may happily make the deal quickly, but most people want to take their time selecting a relationship partner, and they want to be evaluated and chosen with the same care.

3. A hasty attempt to elicit commitment has a vibe of desperation about it.

Like a used car salesman, he doesn’t want you to spend time looking under the hood, and he’s peevish if you want to think about the decision for a while. People with options tend to weigh them carefully, so rushing into a relationship implies a lack of options, and it carries the whiff of insecurity or fear.

4. Women expect to have to compete for a male, winning him over with our feminine wiles and enticing him into exclusivity as we successfully navigate his high standards.

Women do not want to be robbed of this opportunity to compete with other females. If there are no other females competing for him, a guy benefits from holding to his high standards in any case. Having low standards, or worse, none (like our friend in the comic above), is a turnoff to women.