I trust its creator - Former Google employee (and now notable star in the crypto universe), Charlie Lee. And because of its market capitalization, which is $12,491,891,862 (Jan 3, 2018). Moreover, Litecoin is also designed to produce more coins: it has an 84 million coin limit, versus bitcoin’s 21 million. About 54 million coins are currently in circulation, versus bitcoin’s current 16.7 million circulating supply.
I do believe that EOS and Waves are very promising altcoins that will grow in their price very soon and give all of the investors the best profits. I suppose that Ethereum will be also growing up.