So Electrocute doesn't work like Thunderlords?

As Anivia normally Q-Q-E will proc Thunderlords. To be clear, that is:

• Press Q once, and the iceball passes through the enemy, causing damage.
• Press Q again, and the iceball explodes, causing damage a second time.
• Press E, ice spike is cast on them.

That should be three separate hits, right? Yet it doesn't proc new Electrocute. Similarly, letting somebody sit in your ult for multiple ticks, and then casting E on them should also proc Electrocute, but it doesn't. Is this intentional? If so, why?

If it's because now they must be separate abilities then where do you draw the line? Would three consecutive Riven Q's not proc Electrocute because they're all part of "one Q"? What about hitting somebody with multiple Taliyah rocks with one Q? What about multiple hits from a Lucian ult? Only counts at one hit? That'd be silly... I think it'd be easier to make it work like Thunderlords did.