Continuous Product Line Updates

Showers are one of the few truly quiet times I get during any given day.  It's one of the first things I do during the day, so I'm groggily waking up rather than worrying about anything going on in my life.  This gives me a few minutes to think, which usually leads to some pretty random musings.  All that lead up, just to say that this morning I was pondering my shampoo bottle.

I've been using Pantene since high school (and really like their shampoo and conditioner, by the way), but the type/flavor/variety of said shampoo and conditioner seems to change every time I buy it.  This was understandable when Pantene went from one 2-in-1 shampoo/conditioner to a variety of 'lines'.  However, since that point many years ago, there have been a bazillion changes to their lines.  The most recent of which is to design the 'lines' by the type of hair you have.

(Image from Pantene web site at http://www.pantene.com/en-US/PublishingImages/Collections/img_shampoo.png)

While I always still seem to be perfectly happy with whatever 'line' I choose, and at the risk of sounding old, I find it pretty annoying that every time I go to the store to buy another of the shampoo/conditioner type that I choose, I need to figure out which new thing most closely matches the one that I was using before.  It's even worse than companies that change their bottle designs/colors/logos on a regular basis (also somewhat annoying when you're looking for the green bottle which you found, but the one you wanted actually is suddenly purple so you accidentally bought the wrong product).  I mean, I don't think they're actually changing all that much - at least the only real noticeable difference is the name change on the bottle, and maybe a slightly different scent, but it seems to work the same.

This gets me to my musing and a question for all you business/marketing type people out there.  Do companies attract enough new customers without losing any of the old that it's worth it to them to pay design and marketing teams to design "new" products on a regular basis?  Is it less expensive than I think to update the manufacturing components as well?