Combo of GG and Nyc's response,
if you haven't put in the time to EXPERIENCE their bad behaviors and bad habits-you don't know it's love.
It could be, but you don't know.
NRE is a combination of chemicals overflowing in your body-much like smoking crack or doing ecstacy. It feels GREAT (it's designed to). But, it isn't based upon any real compatibility of lifestyles-it's your bodies natural design for motivating procreation.
For me, if I haven't put at least a year in-I won't even consider the possibility that it's more than attraction and NRE.
There's nothing innately wrong with NRE-it's just that it's not dependable. It will wear off (and often times return again! But, we tend to call that ORE).
Something to look at if you are using your question in order to decide the viability of a LONG TERM COMMITMENT (some people like to hop from NRE experience to NRE experience and you don't say specifically why you are wondering);
is what are the FACTS of how you/they operate and are those things compatible when considered for themselves, versus for each other.
I NEED a lot of light (depression issues).
I can't live well with someone who NEEDS the house to be kept dark (a friend has serious health issues due to war injuries that does require this).
I sleep best with LOTS of blankets and the temp around 70-72 F. A partner who sleeps best with something over 75 or under 68 is going to be a problem if we expect to sleep together regularly.
I have kids.
Someone who hates kids ain't going to be compatible with me.
I have ADD issues.
Someone who flies by the seat of their pants in everything-isn't healthy for me.
Etc. (they need considered opposite too-not just self needs, but the other persons needs-I'm just flipping out examples off the top of my head).
clearly it depends upon what type of relationship. Many of these would be non-issues as long as we aren't going to live together-others would matter regardless.
Someone who is only available at night-isn't going to work for me-cause I'm almost never available at night.