Why is the first row in some planes not always Row 1?
 

I'm sure there is a good reason for this but I'm curious about it nonetheless.

I've noticed a wide disparity in row numbers in different planes and there may be a pattern based on airlines but I'm not sure.

For example, a lot of AA aircraft for example start with row 2 or row 3 (757 and 737 respectively) up front. The new AA 777-300ER starts with row 1 - as does almost every Delta plane I have been on.

On the other hand, all BA aircraft I've been on start with row 1 and have Swiss and LH and a few others.

Any ideas?

Why is the first row in some planes not always Row 1?
 

I would have thought the topic for the day would have been why do we still skip row 13

Expanding the subject to why row numbering isn't necessarily consecutive

Theory 1: Avoiding renumbering should F/J/Y seat counts change.
Using a B747 for example, there are many sections if you think of the doors as natural partitions. Some airlines intentionally have large gaps between the last row of one section and the first row of the subsequent section such that if the former section is reconfigured to have an increase in the number of rows, the subsequent sections don't have to be renumbered.

e.g. In the B744 of NW, the section between doors 2L/2R and 3L/3R used to have a mix of C and Y seating. A few years later, it was reconfigured to just have Y.

e.g. Perhaps there used to be a row 1, but it was eliminated when a bathroom or closet was added. And, the airline didn't want to deal with renumbering the rows.

Theory 2: Low numbers are only used for a given premium cabin

e.g. In the regional (intra-Asian) 777s that CX operates, there is no first class, only business class and coach class. The first row number is actually 11, situated in the J cabin. In intercontinental 777s where there is a first class, the first row number is 1, situated in the F cabin.

In case an aircraft is substituted for a close but not identical version, minimizing disruption

Asian carriers seem to always start at 11 when there is J but no F, any idea why?

See theory #2 in my previous post. :) Also, CX sometimes swaps a regional plane with J and Y with an intercontinental plane with F, J, and Y. As another poster mentioned, a common numbering system creates less havoc when an aircraft swap occurs. Also, other widebodies of CX have J starting at 11.

Note that CX skips row 4 and 13. 4 is a bad luck number in Chinese culture. Silly, if you ask me regardless of culture, skipping numbers for superstitious reasons.

Possibly the way AA had the plane put together? the galley and closet usually look to be where the missing rows would be located.

When I posted the question, I had assumed that this is to maintain a kind of uniformity between disparate aircraft types (but I wasn't really sure what this specifically was) but now I see there may be a variety of reasons and customs involved.

The numbering along with seat number is to maintain consistency across airlines models and various configurations and to update their software even when that configuration is long gone is not such an easy task.
(ever notice how ABC is the window - middle - aisle then D... is the middle section even if there are only two seats on the side AB or AC the inside aisle will still start with D on the wide body planes so if you ever get E you can guess where you are sitting no matter the configuration).

There's also usually no seat I owing to confusion with the number 1, so, for example, the seating will be ABC-DEFG-HJK, or AB-DEFG-HJ, or AC-DEFG-HK (skipping J)