Hello everyone,

Mining pool hub said:"...You need to mine with low speed for long period of time.
Also make sure that you do not leave the pool in the middle of mining. (This happens at nicehash frequently because of bid/ask change of hashpower)..."

I'm a frequent user of Nicehash services, what is so wrong about non-continuous mining?
Can someone please help me understand?
 If I have hashing power that comes and goes intermittedly, how does that hurt me? By participating to many more blocks over a longer period of time, shouldn't my earnings be actually more stable than participating to a smaller amount of blocks but in a more continuous way?
Thank you all