Deboer has brought two teams to the Stanley Cup Final. Do I like him, not really. Are there a dozen coaches I'd probably rather have, maybe. Do I think he's nearly as bad as people on this message board seem to believe, absolutely not.
First year coach in each case. PDB brought somebody else's system to the SCF. This suggests to me that PDB is a great at rapport with the players early, but is not the strategic type to develop systems and teams.
Looking closer at his record, Pete's best season points wise with FL and NJ were the first year. All three years at FL, Pete has never won more games that lost. He tied 41W-41L in the first year though.
Next four years at NH, Pete had more wins than loses in the first year (the SCF appearance year), but then had more loses than wins in the succeeding years.
The aberration is the Sharks, but Pete is a mediocre coach at his best, and poor coach at his worse. He's lucky to be coaching in a well-managed organization. Don't confuse luck for skill. This Sharks team is one of the top three teams in Sharks history, and it's a mess. The system is messed up, and not up to NHL competitive standards.
It came in 2nd in the division on the strength of individual talent.
The PP system is even worse.
Sharks have never won the division under PDB. They had a great chance to this season, but it's a mess when they lost 1st place the last time to right now.