How long do you stay in a relationship waiting for a spark to develop?

If you are in a relationship with a great person but you don't feel that spark, how long do you hold on hoping to find it?

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+1 y
Why did I get into this relationship to begin with seems to be a common theme of those responding so it must be time for an update.
I got into a relationship with him because I find him very attractive, we get along well, we have common interests and common values. He's a good person and has the qualities that I'm looking for in a significant other. Maybe I was too eager to be in a relationship when we met, but here we are.
How long do you stay in a relationship waiting for a spark to develop?
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