User blog comment:SirAston/Ye Olde Garde-e/@comment-5556439-20131029220830

Well most of the older champions were designed by some the designers who came from DotA, so their strengths and themes are going to be somewhat "outdated" compared to newer champions because they wanted to bring a slightly weaker power level from DotA Heroes into LoL. Styles and overall ideas also kinda creeped into LoL as did the power levels. This is why most of the older champions have some of the strongest numbers in the League, and have more traditional skillsets.

Mechanics will come and go with the Meta, but there is only so much you can honestly do.