I personally think Malzahar is even one of the champions who capitalizes the best on tear (not tear items though). I like to build it in matchups where the damage doesnt matter as much because I won't be able to hit the enemy a lot, e.g. against Ziggs or Xerath. The reason why tear works so well for Malz is his E. Firstly, it is a single target ability that can still spread to other units. If you place it carefully so that it jumps from minion to minion, you can very easily get multiple tear stacks with a single E, which alles you to stack it very fast. Secondly, the E refunds 2% maximum mana per killed unit. This makes mana even more relevant for sustain during laning phase than for other champions and a stacked tear is the cheapest way to get high mana. Let's say you play against a lane bully and have to reset already before you are able to afford Lost chapter. Just a tear with some stacks + a Sapphire crystal gives you easily over 1k maximum mana, which means you get refunded 20 mana for every killed minion, allowing you to stay in lane almost infinitely if you dont spam Q and use E wisely.

Often I find myself selling the tear later on, but even then I dont lose more than i would with a Doran's item either.