Number 1 - spur of the moment, do I regret it, not really because it is somewhere that is easily hidden.

Number 2 - took about 5 years to find the actual design that I liked for it, then 2 months wait to get into my tattooist

Number 3 - pretty spur of the moment for the design, a months wait to get into the tattooist

Number 4 - idea rattling around in my head for about 6 months, months wait to get into tattooist, probably a bit bigger than I wanted but I love it

Try getting a fake one done and see how you like that, I've done that for where I initially wanted my fourth tattoo but ended up getting it where I got it instead (and much bigger).