Number 12 of The Rules of Cycling says the correct number of bikes to own is n + 1.
According to bike website www.velominati.com, Keepers of the Cog, "while the minimum number of bikes one should own is three, the correct number is n+1, where n is the number of bikes currently owned. This equation may also be rewritten as s-1, where s is the number of bikes owned that would result in separation from your partner."
There was a time, a couple of years, ago when the garage and shed were very full with a baker's dozen, 13 bikes. There was also a 1950s tandem that weighs more than a boat anchor floating around somewhere.
After strict rationalisation that is down to 4 - a long-travel trail bike, a shorter travel cross-country rig, a hardtail singlespeed and a classic grocer's bike. Five if that tandem ever turns up.
There is now room for n+1. This time it's going to be more hands-on than wandering into a bike shop with my credit card. This time it's personal. It'll take a bit longer than an off-the-shelf bike purchase. However, the result will be tailor-made to fit me.