Please offer any insight on the following problem:

Vehicle will crank, about 5 cranks, but each crank is slower until it stops. Waiting about a minute and trying again will either have the same result, or the car will start up just fine. This will only happen about 10% of the time, otherwise it will start up no problem. It seems to be more likely to happen if the car has only been off for an hour or so. Less likely to happen when started after sitting all night.

The battery (Napa Legend) was about 6 months old, and had good reading when connected to a multi-meter. Explained the problem at the shop, they tested and said it was the battery, so I went and got a new battery. Car started fine for about 2 months, now the problem is happening again.

 

The problem vanished for about 6 months. Now that it is 10F degrees outside, I am having the same problems.

Battery tests with a multimeter:
When the car starts: 12.6V cold. It will not drop below 10V when cranking and will stay around 14.2 when running.

When car wont start: 12.6V cold, will not drop lower than 10V when cranking. After it fails to start, 12.2V cold. Fails again, 12.0V cold. Tried again and it starts, 14.2V running, and 12.8V when I turn off the engine.

 

I have a 2008 Accord 2.4L vti & also have a spasmodic cranking issue. Kind of related to yours but not. It began 2 years ago when the starter motor started having issues & so a local mechanic replaced it with an after market starter (cheaper than the Honda branded). The extra cranking started the very next day. To cut a long story short - after multiple mechanics, auto electricians & quite a few replaced parts including sensors AND the battery a few times (some replaced to attempt to fix the issue, some replaced because it was good preventative practice considering the kms & hoping it would fix the issue), I still have the intermittent problem. AND the after market starter motor is still in place. All mechanics & electricians 'felt' it wasnt the after market starter motor that might actually be the problem. (I'm still scratching my head over this & am now considering forking out $$ for either a 2nd hand Honda starter or a brand new one ($$$$$) just to satisfy myself that it is/isnt the possibly faulty/incorrect model afrer market part.
I finally found an older mechanic who has started initial investigation (requesting I not tell him about past works - so that he starts from scratch) & has found that the starter motor is drawing too much voltage from the battery than it should. (Did the auto elecs not test this?) The battery is under 2 years old & in the past, replacing the battery & even its capacity has not made any difference to the problem. This mechanic had a break over january so I'm looking at returning the car to him to continue his investigations