You have 38 big blinds. You're not short-stacked, you're not desperate, but you're certainly not the chip leader.
You're... comfortable.
You can afford to fold a few hands, wait for a better opportunity, maybe even enjoy a coffee without constantly calculating your tournament survival.  And that's precisely where the trouble begins.
In tournament poker, having a comfortable stack can sometimes be more dangerous than having a short one. Chips may not be a problem (yet), and that does something to your decisions.

When survival becomes a habit

Something interesting happens when your stack reaches that pleasant middle ground.
With 10 big blinds everything feels urgent. You know you must find opportunities, and you're constantly looking for a profitable spot to make your move.
With 70 big blinds you have room to manoeuvre, apply pressure, and absorb the occasional setback.
But with 35 or 40 big blinds? You have... something precious to protect.
Suddenly, a perfectly reasonable raise feels unnecessary. Defending your big blind seems dangerous. A playable hand from the button becomes an easy fold because, well, why risk it?
You're no longer looking for opportunities but on the contrary, you are looking for reasons to avoid them.
The most amusing part: you can convince yourself you're playing excellent, disciplined poker.
Sometimes, you are. But sometimes you're simply afraid of becoming uncomfortable again.

The incredible shrinking stack

Here's an unpleasant little trick tournament poker likes to play on us: imagine you have 80,000 chips with blinds at 1,000/2,000. That's a healthy 40 big blinds.
You decide to play cautiously. Nothing dramatic, no unnecessary confrontations. A couple of levels later, the blinds reach 2,000/4,000.
Even if you somehow managed to avoid paying a single blind or ante, those same 80,000 chips would now represent just 20 big blinds.
Your stack hasn't lost a chip, but half of its relative depth has disappeared. And in a real tournament, of course, you're also paying blinds and antes along the way.
That's the problem with protecting a comfortable stack too carefully: the tournament keeps moving even when you don't. The blinds are charging rent, and they never miss a payment.

The difference between patience and fear

Now, before we start shoving every playable hand, there's an important distinction to make: preserving your stack can be absolutely correct.
Near the money bubble or significant pay jumps, the math changes how tournament decisions should be evaluated.
A medium stack facing an aggressive chip leader may have excellent reasons to avoid a marginal confrontation, especially when several short stacks are close to elimination.
Protecting your stack isn't a mistake of course. Though there is quite a difference between folding because the situation is strategically unfavourable and folding because you really like having 38 big blinds.
One is discipline, Tthe other attachment. Attachment is an expensive luxury in poker.

Your chips are tools, not trophies

The comfortable stack offers something genuinely valuable: flexibility. You can raise without committing your tournament life. You can take advantage of position, or pressure opponents who have their own reasons to avoid confrontation.
In the right circumstances, other medium stacks can be particularly interesting opponents, because they may feel the same pressure you do.
So what, now we have to attack everyone indiscriminately? Of course not. An opponent with a short stack might reshove, while a bigger stack can put you in very difficult situations.
The objective is to identify profitable opportunities, not manufacture action for its own sake: think of your stack as a collection of tools:
You didn't accumulate those chips just to admire how nicely they're arranged in front of you. They are useful.

One question that can change your tournament

The next time you're sitting comfortably in a tournament and considering a fold, ask yourself something simple:
Am I folding because this is a bad spot, or because I don't want to lose my comfortable stack?
Then look at the actual situation.
How many big blinds do you have? How quickly are the levels increasing?
Who covers you? Who can you pressure?
Are there meaningful pay jumps affecting the decision?
Sometimes those answers will tell you to fold and sometimes they'll tell you that your comfortable stack gives you an opportunity you shouldn't ignore.
In other words, stop confusing inaction with safety, but don't become reckless. 

Comfort is temporary. Decisions matter.

There's a particularly cruel irony in tournament poker: players work hard to build a comfortable stack, then become so determined to preserve it that they slowly surrender the advantages it provides.
Eventually the blinds catch up, the comfort disappears, and they're forced into exactly the desperate decisions they were trying to avoid.
Of course, this doesn't happen to everyone as dood players understand when preservation is valuable and when aggression becomes necessary.
But the lesson is worth remembering:
A comfortable stack is an opportunity. A means to an end.
And if you spend the entire tournament protecting it, you might discover that the only thing you've successfully preserved is your fear of losing it.