No, there's really not. I've already explained the main variable here: Price.
The other driving variable, which I left to implication, was inertia.
We didn't have a CIO. Nobody from Dell or HP was taking anyone from this company out for golf outings, dinners, strip clubs, or nose beers. We merely bought and used computers, with perhaps 50 desktop systems at peak that slowly rotated over time as needs ebbed and flowed.
We could have switched to HP or Acer even some box-builder with a non-English name instead, and maybe we would have done so if Dell hadn't introduced cheaper products. Who knows. That version of reality never happened.
It sure seems like the introduction of the lower-cost Vostro line strengthened our inertia. I don't know if that was good or bad for us, but it was almost certainly better for Dell this way than in some alternate reality where it went in some other direction.
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Anyway, I looked at Dell's laptop lineup after I read your previous comment. It's a damned mess. But I'm not sure that this mess qualifies as 70 or 100 (or whatever) base models: It's plainly evident that there's a lot of overlap within this list. :)