Google claims that YouTube ROI is higher than TV ads in 77% of campaigns. 

That's quite a difference. The case study seems to be pretty reliable carried out by various research parties, looking at 56 case studies across 8 countries.

With more and more of us consuming video online, it makes sense that YouTube has a higher ROI and that's where the budget should be going.

However it's probably worth viewing this stat with a pinch of salt. YouTube is one of Google's subsidiaries, so it makes sense to present online TV ad spend more favourably.

In any case the first thing we should ask when looking at ad spend is what is the point of the advert? What do you want to achieve? Many car companies have TV ads to maintain the prestigious reputation so they can maintain the expensive price tag. The focus is not to directly get a sale off the back of one of their ads. 

Remember what your aim is and plan accordingly.