Which is better? ES or YM

Very simple question. And I know its been asked many times before. But which is better, ES or the YM?

Does volume = volatility?
if so would you say that the ES is better to trade since it has higher volume?

The YM has significantly less volume then the ES, but I have heard from many sources that the YM is better to trade because its a little bit more predictable.

I am always thinking that since YM has less volume and many day traders trade the YM, it makes it a more competitive environment.

Can someone shed light on this please.
Thank you.
IMHO.....It depends on how you trade......
With or W/O stops? With or without a helmet? (Protection)

YM trades better technically (off of trendlines, pivots, and averages) but options only trade during the day......ES is more unpredictable as there are so many hands in the pot.....ES Options, SPY, Spy options, other 2X ETFs etc.

Liquidity is important and ES is the most liquid.....as far as volume, tight B/A spreads, options 24 hours/day...

I actually prefer NQ, it outperforms ES and YM, and has options but not as liquid as ES. I wish, but ES is the best in that department......sometimes I even hedge YM and NQ trades with ES options because its more liquid, and the best pricing is usually after hours.

And volume does not = volatility. Can volume move a price? Yes....but balanced volume (upticks v. downticks) actually reduces price volatility. Some of the most volatile pricing comes after hours when volume is very low.
Thanks for the response.
Looks like I'll have to keep an eye on both and trade the one where an opportunity arises.