Before you say anything - I've lived a sheltered life and do not have the dating experience you have, in spite of the fact that I'm up there in age.
There was only one, and I mean one, time in my entire life where I thought when I met this one man, that it was an instant feeling in my heart that if he were available (and not a scrote), he would be the one. It was immediately when I met him.
(OK it turns out that he wasn't the "one" but I'll make my point)
Do you feel you need to know "right away" when you meet a man that he is the one, or do you need to give it time? If you feel absolutely nothing at first, do you need to wait for a spark? I hope it doesn't sound like a "give him a chance" thing - I always hated that and still do.
This spark is usually not healthy.
It tends to be childhood trauma (ex. codependency) being activated. This feeling is a warning sign. Healthy relationships start slow and progress organically.
You do need to give it time, but you don’t need to give a chance to someone you feel absolutely nothing for.
For me it usually starts with “Hm, he’s handsome,” or “Hm, there’s something interesting here” that will lead me into the first date. If I feel nothing at all, he won’t even get the first date.
Then, the first date either continues my interest or loses it. And if he continues my interest, then it’s just regular vetting from there on out.
From past experience nothing good ever came out of liking a stranger immediately aka having that spark. I think in most cases it was lust or wanting to be close to that person, but not really knowing why, because after all it's a stranger.
I'm not sure if a person can grow on me over time, if there's no initial spark.
I've stopped dating last year. But in general I'd say to be cautious. Get to know someone over a longer time and see how the person behaves in different situations.
For me the spark is an instant attraction and is what guides me in dating. If I don't feel a spark then I'm not attracted and I don't bother. I don't let the spark be the end all be all tho, it's just a ping on the men who my body finds to be compatible. The true test is flirting and seeing if it actually leads anywhere with my brain and heart, not just my groin.
Actual love takes time to develop and build. You cannot be in love with someone you've only met, but you can lust after them. That's why imo the spark is just part of compatibility. You shouldn't be with a man you don't find attractive and while maybe some women can look at an ugly man and choose to care more about his personality, it makes sex and not resenting him hard.
You should be attracted to the guy. That said, "the spark" is sometimes chemistry deliberately created by LVM has ulterior motives. Think of all those scammers who are smooth talkers.