Hashrate

Hashrate measures how much computational work the network's miners are collectively performing. It doesn't make blocks arrive more predictably by itself: Zcash's mining difficulty continually retargets so blocks land near the network's ~75-second target on average regardless of the network's absolute hashrate level, and block-to-block timing still varies randomly around that target either way. What a higher network hashrate actually buys is security — the chain becomes more expensive to attack, since an attacker would need to out-compute that much honest mining power to rewrite it.

For an individual miner, hashrate share (their own hashrate relative to the network's total) determines their expected share of block rewards over time — mining alone with a small hashrate share means going long stretches without finding a block, which is why many miners join pools instead.