Making adjustments on one shot wastes a lot of ammo. We're not talking benchrest rifles here. A click is 1/4 MOA usually and a lot of guns might be shooting and inch, inch and a half.
This is not the case in my experiece. I generally have a rifle right where want it to be @100 yards on the 3rd shot.
I start at 50 yards and fire 1 shot. If I can look through the bore for the first shot and adjust before firing that is fine, even if I cannot such as with a lever action I just fire. Where the bullet hits does not matter. If I'm pretty close I adjust and fire shot #2 at 100 yards.
I cannot see wasting ammo with 3 shot groups yet. Even if I'm dealing with a 1.5 MOA rifle the 1st shot will be no more than 3/8" off true zero at 50 yards and no more than 3/4" off at 100 yards. All I'm trying to do at this point is put a hole in paper. If you can see through the barrel, such as with a bolt gun the 1st shot will be pretty close. The 1st shot fired from the last 3 scopes I zeroed last summer.
If you cannot sight through the barrel, just use a larger target. Poster board sells for $.28 at Walmart and you cannot miss something that big. Move in to 25 yards if necessary.
After my 1st shot at 50 and making adjustments I fire a 2nd shot at 100 yards and again make adjustments. I let the barrel cool for a few minutes then fire my 1st 3 shot group. 90% of the time no further adjustments are needed, at least until I back up to 200 yards or farther where I may need to fine tune things.