You never want to seem desperate. You never want to be desperate. You always want to have all the big things planned out reasonably and turning out exactly as conceived years ago.

You want to be calm, calculating, and chuckling at all those teams scrambling below you by early May. You want to be … well, the Dodgers.

However, you also don’t want to stink like the Giants have stunk for more than a month at the start of this season; and you absolutely can’t tolerate the possibility of stinking in exactly the same way for another bunch of weeks — just in time to ruin an entire season.

It can get late awfully early if you’ve gone four consecutive seasons without a playoff berth and your large fan base understandably keeps reminding you of that after every shutout loss ...

If you’ve sunk a ton of money into Rafael Devers, Willy Adames, and Matt Chapman, who combined for a mere six home runs and 0.2 bWAR through the first 35 games of the season and all look worryingly vulnerable to high-mph fastballs …

If you consistently can’t score runs — and if your bullpen blows it most times when you thought you’ve scored just enough.

That’s why I not only understood why Buster Posey shook up the roster on Monday — calling up top prospect Bryce Eldridge and catcher/utility man Jesús Rodríguez — I wondered why it didn’t happen a little sooner.

Both players went right into the starting lineup (Eldridge as the designated hitter, Rodriguez at catcher), neither got a hit, but the Giants beat the Padres, 3-2, to open this homestand. Neither looked completely overpowered by fastballs, either, I’ll point out.

And I suspect the proper and necessary message was sent and received: Lineup spots can’t be granted on scholarship, even if the invested dollars suggest otherwise.

Clearly, there’s no guarantee that Eldridge will be better than the struggling veterans. But it’d be very hard for Eldridge to be worse than those guys. Same for Rodríguez’s offense at catcher or any other position.

Which is more important than anything else; getting the best at-bats possible is, by far, the most important issue here.

And if the duo’s presence sends an electrical jolt of competition throughout the clubhouse, that’s all the better for the Giants.

On Monday, Chapman and Patrick Bailey got benched; I presume that Adames, Devers, and Heliot Ramos will have turns there, too, perhaps starting Tuesday. Unless one or all of them get hot. Unless they earn their way back into guaranteed lineup spots.

Now, we can all land proper criticism of Posey and his front office for acquiring all these players who may or may not already be sunk costs. And it’s true that Devers and Adames both had big surges last season specifically after big slumps.

But high-priced players who go through enormous slumps every season are not really that valuable. Certainly not valuable enough to save them four at-bats a game for months on end while their OPS hovers around .600 and the team falls further and further down the NL West ladder.

If the Giants weren’t going to make changes now to try to save the season, when were they ever going to?

Sure, there’s a risk here. If Eldridge, in particular, feels too much pressure under the spotlight, loses confidence, and has to go back to the minors, that obviously would not be a good thing for the future of this franchise.

But Eldridge didn’t sound too flummoxed before the game on Monday, when he relayed what he told Jared Oliva earlier in the day: “I’m feeling sexy at the plate right now.”

Also, here’s a thought: Eldridge might be good right away. He might force opposing pitchers to think about something other than just blowing three fastballs past every middle-of-the-order bat in the lineup. He might upgrade the Giants’ offense just enough that things feel very different.

I recall a big early-season move 16 years ago — May 29, 2010, to be exact — when Brian Sabean shook up a meandering season by bringing up Posey. A month later, the Giants brought up Madison Bumgarner.

It all sort of worked out, I seem to recall.

On a much more moderate level, last June, Posey traded away his old teammate LaMonte Wade Jr. and added Dominic Smith and, at least for a time, injected some energy into the Giants. (His big trade for Devers came a week later. To lesser results.)

I’ll repeat: Knowing Posey, I’m a bit surprised it took this long. He’s loyal to his guys, but he’s shown that he can make quick decisions and that he likes the impact of them.

But I also suspect that Tony Vitello, infamously coming into this season without a day of MLB experience, logically was determined to stick with his proven guys for as long as possible. He didn’t want to walk in from Tennessee without fully respecting and backing the MLB veterans who’ve earned these spots. Casey Schmitt and Jung Hoo Lee have rewarded Vitello for it. Others definitely have not.

I mean, Vitello’s patience with Ryan Walker, who probably got about four more save chances than most other managers would’ve given him, was a major show of empathy and understanding. But Walker isn’t the closer, anymore. That decision finally happened during that last 0-6 road trip.

And now Eldridge will get regular at-bats, either at DH or first base. Rodríguez will get ABs at catcher and all around the field. Once Daniel Susac is healthy, Bailey might not keep his roster spot.

There are a lot of things happening. They should be happening. This is when these things have to happen.

Also, this popped up on social media on Tuesday, courtesy of Baseball America:

The Giants’ farm system, for the first time since the Posey-Bumgarner-Tim Lincecum-Brandon Belt-Matt Cain run, is healthy again. There are a lot of valuable prospects.

I’m noting this because this — plus the No. 4 pick in the upcoming draft — gives Posey options. He could let Josuar Gonzalez, Luis Hernández, Gavin Kilen, and the rest all work their way up and plug them into main spots on the big club next to Eldridge and maybe Rodríguez by 2028 or so.

Or Posey could trade one or two of them for something good before the trade deadline. Or for something good plus the chance to get off of a bad contract. Or two bad contracts.

Is it too early to be thinking like that? Maybe it would be for the Dodgers, Yankees, or Cubs. But not for a team that finally showed this week that it knows exactly where it is, how it got there, and what kind of thinking is necessary to get it out.