What Are the Negative Consequences for a Miner If the Pool Sets the Share Difficulty Too High?

If the pool sets the share difficulty too high, a miner will submit shares very infrequently. This increases the statistical variance in their short-term earnings, making their income highly unpredictable.

For a low-hash-rate miner, it could mean days without submitting a single share, making it difficult for the pool to accurately track their contribution and for the miner to assess their performance.