Define a good player

[Shurrikhan]

One who can keep the final win condition (e.g. clearing the encounter, by whatever means best achieves that as quickly as possible) in mind and remember to always process backwards from that, but can also readily identify all or the vast majority of nearer win conditions applicable to him (cost balances, sync, uptime, cleave, etc., etc.), and can maintain the focus necessary to execute appropriately upon most of them.

In other words, if it doesn't at least indirectly clear the encounter more assuredly or quickly, it's not relevant, but anything that does cannot be dismissed just due to preconceptions or nearer win conditions; the nearer win conditions should be reconsidered to ensure they're the best match for what's actually necessary.

If a player can understand and make use of that, they tend to be a good player, whatever the game.