Last week, I wrote about the new danger signs around BlackBerry's current comeback attempt, including the lack of carrier support for its new BlackBerry Classic smartphone. [Updated 2/16/15: AT&T said today that it would begin selling the BlackBerry Classic and Passport on Feb. 20.] [Updated 2/24/15: Verizon Wireless said today it would sell the Classic on Feb. 26. But it announced no plans to carry the Passport.]

BlackBerry fans were outraged, with some taking my analysis as a personal attack on their choice of the BlackBerry platform. Some resorted to the worst impulses of a fan, with the Internet's modern equivalent ("you're an Apple fanboy") of the "your mother wears combat boots" insults from the era of my boyhood.

That's childish emotionalism, but what struck me was the number of wishful-thinking arguments that BlackBerry the company and its ardent fans having been making for years. A set of delusions has let BlackBerry become endangered and will finish off the job if fans continue to believe them. BlackBerry needs a realistic strategy if it hopes to prosper again, not more delusion.

Delusion No. 1: BlackBerry's problem is a marketing failure

One delusion is that BlackBerry's products are amazingly attractive, but bad marketing is hiding that fact from the world. With good marketing, everyone will abandon their iPhones and Android smartphones for a BlackBerry. After all, that's what these users did.

Marketing can get people to consider a product and reinforce that you made the right choice earlier (so you buy again). But marketing can't make people buy something they don't want.

Contrary to claims by desperate fanboys, people aren't buying iPhones because they are "iSheep" seduced by marketing for "overpriced" smartphones. In fact, outside the United States and Japan, people are buying Android smartphones, whose prices range from cheap to iPhone-level. Are those people "aSheep"? (For the record, when it comes to smartphones, in the United States, it's basically half iPhone and half Android.)

Those people are also not buying an iPhone or Android device once, then seeing the error of their ways. No, they buy them again and again, with a minuscule number returning to BlackBerry. Marketing won't trump such personal experience and the word of mouth that results.

Yes, BlackBerry 10 has compelling capabilities, but not enough to compete with iOS, Android, or even Windows Phone.

The truth is that BlackBerry has a product problem, and it's not clear it can solve this problem: BlackBerry fans rejected the touchscreen Z10 in 2013, as well as the keyboard-oriented Q10 that year. That rejection cost BlackBerry more than $2 billion in write-offs. Instead, BlackBerry fans bought the old-style BlackBerry 7 devices -- suggesting they want no modern smartphone technology at all.

That leads me to suspect there'll be few buyers for the new BlackBerry Classic, which puts the BlackBerry 10 OS on the beloved BlackBerry Bold hardware design -- exactly as the Q10 tried.

Only in the last few months did BlackBerry finally run out of the old models, though they're still available at some carriers. Going forward, you'll have to buy a BlackBerry 10-based model if you want to get a new BlackBerry.

We'll see how many actually do -- the fact that neither AT&T nor Verizon Wireless is selling the BlackBerry Classic is a bad omen, though both say they will at some point.

Delusion No. 2: BlackBerry's struggles are a U.S. phenomenon

BlackBerry fanboys like to say it's all blue skies outside the United States when it comes to BlackBerry adoption. But if you look at the sales data for BlackBerry for 2013 and 2014, you'll see that BlackBerry sales are heading only one way: down.

Sure, in some countries, there was a slight uptick in BlackBerry sales when the company released its first BlackBerry 10 devices, the BlackBerry Z10 and BlackBerry Q10. But the slide continued soon after. People looked at the new BlackBerrys when they debuted in spring 2013, then resumed buying other devices.

Kantar Worldpanel's data on smartphone sales in key markets shows this trend clearly. I've created a chart showing BlackBerry sales trends for two years in key markets; in not one has BlackBerry grown, and in most markets its share of sales is now less than 1 percent.

Mexico and Argentina are the noticeable exceptions, with market shares in the 4 to 5 percent range, but even there BlackBerry sales continue to fall relative to the market as a whole. Mexico's pattern is very similar to that of Argentina as shown in the chart below: a steep, sustained drop over two years. Australia's, Brazil's, Japan's, and Spain's patterns are similar to that shown in the chart for China: near-zero market share for both years.

In no country are BlackBerry device sales growing. (Data: Kantar Worldpanel)

Delusion No. 3: iPhones and Android smartphones are toys

You hear this argument mostly from IT staffers: People don't need apps on their phones; they're time-wasters and potential data leakers, after all. That of course is why 99 percent of the world isn't buying BlackBerrys, right?

BlackBerry co-founder Jim Balsillie made the same statement in 2010, three years after the first iPhone and two years after the first iOS apps. His self-delusion is a key reason why BlackBerry continued making messaging devices for email and texting, not true smartphones. It's also why people stopped buying BlackBerrys.

Today, that delusion has put BlackBerry in a very bad position. Few apps are available for BlackBerry devices, so they're not attractive to users. Additionally, the IT folks who hate apps reinforce the message to managers and users that BlackBerrys aren't real smartphones.

When the BYOD movement took off in 2011, it should have been a clarion call to both IT and BlackBerry that users wanted apps -- that's why they defied IT and brought in iPhones and later Androids, and why most organizations have since adopted iOS as the standard mobile platform. Even the U.S. Defense Dept. has approved iOS (when used with appropriate management servers) for most government users. Today, BlackBerry the company believes in apps, but many of its ardent fans don't.

That attitude leaves BlackBerry's potential business around secured communications. That's certainly necessary for some people, but not for the vast majority of users. BlackBerry's own fans are limiting the platform to highly sensitive users, such as presidents, defense contractors, and spies.

Delusion No. 4: BlackBerry doesn't need devices to succeed

The current BlackBerry CEO, John Chen, has said he'll get rid of BlackBerry devices if they don't become profitable. That's reinforced an attitude that BlackBerry can succeed on the strength alone of its BES12 mobile management server or maybe of its QNX Internet-of-things operating system.

IoT is a small market, especially at the infrastructure level that QNX inhabits. It's a great business for making a few hundred million dollars a year, but BlackBerry has been a multi-billion-dollar business.

BlackBerry's current BES strategy is to get all those companies that use BlackBerrys to adopt BES to also manage their iOS and Android device, since roughly half of businesses use the older BES5 version for their older BlackBerry devices.

The strategy made a lot of sense a few years ago, when companies were first allowing iPhones and Android devices in and needed a mobile device management (MDM) tool. But BES back then was BlackBerry-only, and nearly 100 companies jumped into fill the gap.

Today, any large company that needs iOS and Android MDM has it, typically from Citrix Systems, Good Technology, IBM, MobileIron, or VMware. These companies have also moved beyond strict device management into application and content management, areas where BES12 doesn't have a strong play for iOS or Android.

In the BlackBerry heyday, BES had the advantage of being tightly integrated with the BlackBerry device hardware, the BlackBerry way stations at carrier facilities (NOCs, or network operations centers) and the BES server itself. But those advantages don't exist for iOS or Android, where BES12 is another MDM server with access to the same OS-level APIs as everyone else. BlackBerry can do special things in iOS and Android using container apps and direct integration with specific apps, but so can (and do) its competitors.

As the number of BlackBerry devices continues to shrink and with iOS- and Android-savvy MDM servers already in place, what's the motivation to use BES12 instead of those servers? One motivation would be a growth of BlackBerry devices; IT would then have two MDM servers in place and might be able to justify consolidating into one. But it means BlackBerry needs to sell more devices, at least to corporate users. That's not happening. BES12 needs BlackBerry devices to justify its existence.

As for all those companies (perhaps 80 percent) that have no MDM server but instead use nothing or Exchange Server's core policies, BES12 is no more attractive than the other MDM servers, and the highly promoted Balance/Secure Workspaces, Blend, VPN Authentication, and Messenger features come at extra cost. It quickly becomes an expensive option for small and medium-size businesses.

BES12 makes a lot of sense for high-security companies that rely on BlackBerry devices for critical communications and use iOS, Android, and Windows Phone for lower-risk activities. But there aren't a lot of such companies.

Delusion No. 5: Security needs will pull customers back to BlackBerry

If this thinking were true, nearly everyone would be using a BlackBerry in a corporate context. But they don't. Users may have forced iOS and Android onto their IT departments, but if those devices were not secure enough, they would have never broken past IT's defenses.

IT may claim security concerns, but the truth is iOS is secure enough for all but the highest-level needs. Android has many gaps, especially around malware, and Windows Phone lacks key capabilities for security and management. But all can be secured at a basic level, and IT can use other technologies to secure corporate data. Plus, none of these OSes is less secure than Windows, which almost every company uses as its computer standard despite the high cost of malware remediation and data loss.

Again, if security were the real issue, Windows and Android would not be allowed at all in Internet-connected environments; Macs, iPads, and Chromebooks would be the standard computer devices; and Windows Phone would be severely restricted.

As I noted earlier, BES12 doesn't better secure iOS and Android than the major competitors do, so there's no advantage to standardizing on it unless you have a significant base of BlackBerry devices, too.

President Barack Obama needs a BlackBerry's high security, but most people don't.

I don't know what BlackBerry can do to grow again -- I wish I did. But I know that BlackBerry fans, and BlackBerry the company, need to stop deluding themselves about the platform they love. They won't save it with delusions.