The marijuana industry has delivered one milestone after another in 2018.

The highlight, of course, was the legalization of recreational cannabis in Canada on Oct. 17, 2018, which ended nine decades of adult-use prohibition. However, we also witnessed two more U.S. states legalize medical pot, which went along with Michigan becoming the 10th state to OK recreational weed use. Add in pot stock uplistings, the first cannabis-derived drug being approved in the U.S., and Tilray becoming the first pot stock to IPO on a reputable U.S. exchange, and you have the makings of a groundbreaking year.

Canada's privacy commissioner is planning to issue guidance for buyers and sellers of legal cannabis amid ongoing concern about potential fallout, such as being barred from the United States, if transactions become known by third parties.

The concern has been heightened in provinces where anonymously paying cash in-store is not possible in light of a controversial Statistics Canada initiative to obtain detailed bank records from all Canadians.

In the days following the legalization of recreational marijuana in Canada, HEXO was quick to send out a press release touting its ability to meet demand where other companies had fallen short.

In the early days of legalisation, James Burns was confident his company had enough product on the shelves of its five new cannabis retail stores, even though they only received half of their order from the provincial supplier.

Now, he has had staff refreshing the government supply website in the early hours to snap up scarce new stock as soon as it's available, and is considering restricting store hours.

"While there was product to order we were very comfortably getting a large amount of it," says Burns, the CEO of Alcanna, a company that owns a chain of private liquor stores in Canada and the US and, now, cannabis stores in the province of Alberta.

Aleafia Health Inc.(TSXV:ALEF), based in Toronto, is a licensed cannabis producer that owns Canada’s largest network of medical cannabis clinics. The Company describes itself as a seed to patient licensed producer. It has vertically-integrated capabilities that enable it to cultivate, process, conduct independent medical research and market through its clinics with a physician-led approach.

The Aleafia team is led by former government and law enforcement officials, expert growers, and successful entrepreneurs. With 22 clinics coast to coast in Canada, Aleafia has built a customer base of 50,000 patients.

When Canadian provinces across the country came up against shortages of marijuana in the first month of legalization, it was frustrating. But even more frustrating is that this current lack could last for years.

According to Khurram Malik, CEO of Biome Grow Inc., the shortage is not only due to delays in licensing, but is also partly caused by the strict regulations on the country’s 132 licensed producers and enforced by Health Canada. The time needed by cannabis businesses to come up with a product that’s not only up to par, but is also compliant is standing in the way as well. These are problems projected to persist into the foreseeable future.

The prescription of cannabis for medical purposes – without the need for a special permission – was legalized in Germany in March 2017. Since then, a wave of approvals for medical cannabis has swept across Europe, with many countries following in Germany’s footsteps.

Pot stocks have been trading at very high multiples to sales for a long time and even a lack of profitability has done little to curb excitement in the industry. However, we’re starting to see signs of that changing.

This week, many marijuana companies are reporting their earnings, and the results have been very telling, as investors have not been buying up stocks that have simply achieved strong sales growth.

On Tuesday, Cronos Group (TSX:CRON)(NASDAQ:CRON) released its quarterly results, which showed sales rising by 186% year over year. However, the company reported a net loss of over US$7 million, which was a big drop off from the profit it achieved a year ago.

The supply shortages that have plagued many provinces in the first month of legal cannabis will likely persist for years, industry insiders say.

Provinces including British Columbia, Alberta, Manitoba, Saskatchewan, Quebec, Nova Scotia and New Brunswick have all reported varying degrees of shortages.

It could be a $146 billion sector in less than a decade, but for investors whose interest has been piqued by cannabis stocks, there is still no reason to rush into the publicly traded companies.