Why is Mac OSX 10.6.8 not supported with Symphony ThunderBridge

The minimum OSX version supported for ThunderBridge is 10.7.5, During development, many unsolvable issues unique to 10.6.8 and ThunderBolt were encountered, and it was determined that the vast majority of people purchasing Apple's new Thunderbolt-equipped MacBooks and iMacs would not choose to run 10.6.8.