On March 29, Samsung will announce its latest flagship smartphone, the Galaxy S8.

I won't buy one.

But not for the reasons you'd think.

It's not because I'm scared it'll catch fire.

It's not because I'm disappointed by all the photos and specs that have leaked. (They look pretty great.)

It's not because I generally prefer a different brand like LG, Moto or Apple.

It's not because I've cracked the glass back one too many times. (I've never dropped one, thankfully.)

No, I bought the Samsung Galaxy S6 and Galaxy S7 because I thought they were the very best phones out there, with the best cameras, the best design and the most capabilities -- and I imagine the Galaxy S8 will be just as impressive out of the gate. (Stay tuned for CNET's full review.)

But I don't want a phone that's only the best at the time I buy it. I want a phone that lasts. And I want a phone I can take to any cellular carrier -- because I'm tired of Verizon or T-Mobile using my phone as leverage against me. My Galaxy isn't that phone.

After spending a year with a Galaxy S7, these are the five reasons I'm ditching Samsung.

Enlarge Image James Martin/CNET

1) Battery

After one year, my battery never lasts the day. With a Galaxy S7 -- the same phone we praised in a CNET battery test -- I'm lucky to make it to lunch with 30 percent of the battery's charge remaining. If I don't charge while I'm at work, it dies before dinner.

(It's typical for battery life to dwindle with use and with time -- we weren't wrong with our out-of-the-gate tests -- but this feels excessive.)

I've tried uninstalling apps and I've tried wiping the entire phone, but the battery meter shows a rapid decline no matter what I'm doing.

It feels like deja vu, because the battery was the main reason I gave up my Galaxy S6 for a Galaxy S7. I won't make the same mistake again.

Update, March 29: Samsung says the S8's battery won't wear down as quickly, though.

2) Speed

Andrew Hoyle/CNET

One year ago, there was no question in my mind: the Samsung Galaxy S7 was the phone with the best camera. Not necessarily because of raw image quality, but rather how fast I could snap a picture. Just double-tap the home button (even with the phone asleep) and boom -- ready for action.

But -- like other functions of my phone that used to be speedy -- that supreme shutterbug speed has vanished. Now, there's always a substantial lag before I can take a picture.

Again, I tried removing apps thinking it might solve the issue. I factory reset the entire phone. I installed the Android 7.0 Nougat update. Nothing has brought my Galaxy S7 back to its speedy original state. (I'm not the only tech reviewer who's anecdotally seen this behavior from Samsung phones.)

Most of the time, my Galaxy S7 is still speedy enough to use -- but it's to the point now where the whole phone sometimes freezes for a split-second when I'm typing on the touchscreen keyboard, or dismissing gobs of notifications.

Yuck.

3) Bloatware

Which brings me to the likely culprit for my speed and maybe even battery drain: unwanted Samsung software.

I wasn't kidding when I wrote, in my review of the Nexus 5X, that Google's budget phone felt nearly as fast as my Galaxy S6 despite its notably slower processor. And that was when my Galaxy was relatively new. The reason was pretty clear: Google doesn't install all kinds of unnecessary apps like Samsung. (Why would I use Samsung's sub-par web browser, calendar or voice assistant when the stock Google versions are so much better?)

And with the new Android 7.0 Nougat update, which recently started rolling out to Galaxy S7 phones in the US, Samsung somehow couldn't resist adding even more features that seem useless -- like the Performance Mode which bizarrely only reduces your phone's screen resolution (I didn't notice a difference in speed) until you change it back.

Here's a short list of Samsung apps and features I never use:

The Samsung web browser

The Samsung email client

The Samsung calendar

The Samsung app store

The Samsung gallery app

The Samsung memo app

S Health

S Voice

Samsung+

Samsung Smart Stay

Samsung Cloud

Samsung Pass

Samsung Gear (Samsung assumes you're going to buy their watch)

Always On Display

Multi Window (updated for Nougat)

Video Enhancer (new for Nougat)

Performance Mode (new for Nougat)

To be honest, even the Samsung-exclusive features I appreciate -- like Samsung Pay and the Samsung Gear VR service -- feel like things I could easily do without. After months of trying to use Samsung Pay, I found it was usually simpler to just whip out a credit card, and my phone overheats too quickly to use the Gear headset for more than the occasional "what's new in VR?" refresher course.

4) Carrier lock-in

I paid full price for an unlocked Galaxy S7 at T-Mobile, assuming I could change carriers in the US at will. Too late I discovered that Samsung's playing the band game -- where you have to buy a totally different version of the phone for each carrier, because each model is conveniently missing support for certain specific LTE cellular radio bands which are necessary to switch over.

Might there be another reason why they do that? Sure. But it sure doesn't seem to stop Google, Motorola, and -- yes -- even Samsung from shipping phones that seamlessly support all four major US carriers.

Sean Hollister/CNET

So why, you might ask, is it a dealbreaker for me to stick with a single carrier for the life of my phone? Because late last year, on the eve of my daughter's birth, T-Mobile wasn't there for me when my Galaxy S7 wouldn't stop rebooting. They refused to replace it with anything but a refurbished phone, even though refurbished phones wouldn't ship for a minimum of two weeks.

It took four hours of yelling over Twitter before a rep finally, begrudgingly agreed to send me an ancient Note 4 as a loaner and even then they made it crystal-clear this was a special exception for me.

I vowed right then to leave T-Mobile, because customer service was my main reason to stay. But they knew full well I couldn't make good on that threat anytime soon, because Samsung built my phone this way.

5) Software updates

I won't dwell on this point (you've probably heard it a hundred times) but here we go anyhow: Samsung and their carrier partners are always months late with the latest Android software updates. I just barely got Android N on my Galaxy S7 this month -- but if I'd bought a Google Nexus 5X or 6P, I would have been using it seven months ago!

Plus, it's a little hard to be excited about my Android N update now that Google's already announced Android O.

Josh Miller/CNET

My choice is clear

My Samsung Galaxy S7 isn't a bad phone. Not by a long shot. But this makes twice (my Verizon Galaxy S6 and now my T-Mobile Galaxy S7) that Samsung has let me down. No matter what Samsung announces on March 29, I have no reason to believe things will be different this time around.

Sure, there's a snowball's chance in hell they proclaim the Galaxy S8 will come with stock Android and support every LTE band simultaneously, but I'll bet $100 it doesn't happen this year.

So as soon as I can stomach the cost of another phone, I plan to defect. I'll buy a Google Pixel with Google's Project Fi service -- from the Google Store, too, so I don't end up like my colleague Dan.

Then, for the first time in memory, I won't be subject to the whims of a cellular carrier.

Maybe, a year from now, I'll come to regret my choice. But I think it'll be grand.

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