User blog comment:Emptylord/Blogs/Reworked Runes (2015)/@comment-4022742-20150518073358/@comment-4022742-20150520114738

Most players might not take it, and would probably have more incentive to do so with a buff. However as it is now the number is balanced in conjunction with base stats and growth stats for each specific champion.

If you suddenly increase the amount that people can augment their replenishing resources it is going to spike and slightly skew power in a possibly unhealthy way.

For example power to spam  is restricted by the limitation of only being able to do so once every 25 seconds if she is out of mana. Your small change turns that into once every 23 seconds, or the same as a level 2 Karma. It's small numbers, but it's a power (dps) increase that slightly offsets the balance that Riot is maintaining now. And keep in mind that they have a habit of shaving off 5 damage of a skill or shifting a skill that does 60 damage on level one to 75. Small numbers can make a huge difference.