True, but there's another math. Maria can license Lightroom 5 for the cost of about one year's rental of Lightroom CC and Photoshop CC. Aside from the fact that Lightroom 5 might meet her needs for six years, she also has limited her financial obligations while at the same time can acquire a perpetual license that never expires.
I don't drink coffee but I'd be willing to bet that all the coffee-drinking addicts of the world would vote for the coffee.
It's a low cost only if you also need Photoshop CC regularly. If you need Elements only occasionally, it's a significantly higher cost, especially over long periods of rental payments.
Its reputation is that it is a lot more complicated to use than Elements, which is why I recommended licensing Elements if and when she needs it.
On the other hand, if she instead purchases the perpetual Lightroom license, for an extra $5 during that first year she can use it forever.