This is a good card.
That's my opinion to begin with. It's good. Not exceptional, not great, not an auto-include. And yet, I've seen this card on a list of worst cards in the game, and I've seen people argue it isn't even worth running with Practice Makes Perfect despite the synergy. Naturally, I disagree.
Obviously, the reason people are so down on it is that it compares poorly to Eureka!, to Perception, to several other excellent Seeker skills, and even to Unexpected Courage. The problem is, while Plan of Action is good, those are great, excellent, or auto-includes. It can be a Perception, with one less icon, with a limited window to be committed. It can be an Unexpected Courage, but not in the mythos phase, and not if you want to test certain skills first or last. Eureka is almost a wild icon, and does better than draw you a card.
However, while you could simply see it as a worse Perception, Eureka, or Unexpected Courage - something I generally agree with - it is important to note that it is all those things simultaneously. If you need a worse Unexpected Courage, it's there. If you need a worse Perception, it's there. Is that versatility worth a deck slot? Maybe. Is the versatility worth anything if you're only planning to use it as a deck-filling cantrip? I think so.
Talking theoretically, we can imagine a practiced skill with a single that draws you a card if you succeed. This card would be objectively a worse Perception, and yet I think it would still see some play in a number of Seeker decks. I would certainly run it on occasion. Expand this out to be a icon instead, and it this theoretical card would be a much more likely include. It would still mostly get thrown onto investigates to be a +1 in most of the decks it ended up in, but it would be a skill that competed with Eureka - a worse draw effect, but its ability to be committed to , and its traits would see it out. And there's no reason you couldn't run both. This theoretical card is still not objectively better than Plan of Action. It does have less versatility, and it isn't hard to engineer a second action investigate in Seeker. Any deck that would run this theoretical card - at least at level 0 - has a reason to consider Plan of Action. Any deck that wants to go skill and draw heavy for whatever reason should at least consider it.
And if you need to fill a 45 card deck with as many cards that replace themselves as possible, you can do a lot worse.