How does 'luck' affect solo miners?

Hey Guys,

When I go on coinwarz to calculate the profitability of some mining setup, it always give an approximate time to solo mine a block (i.e., "Days to generate one block mining solo: 19.88 Day(s) (can vary greatly depending on your luck)".

What's luck have to do with it?

Hypothetically, let's say I have enough hash power to solo mine a block approximately every 20 days. For the sake of argument, let's say that one block is worth more than I would make mining in a pool for an entire month. Wouldn't it be more profitable to solo mine?

I can understand some variance (maybe some blocks take 30 days, maybe some only take 15), but how crucial is this "luck" element that can't be accounted for? Could it screw me over?

If I could solo mine a block in approximately 20 days, what are the chances that I go 60, 120, 365 days not mining a single block?

Submitted August 31, 2017 at 12:32AM by toothpasta1 http://bit.ly/2xynXUX