We all have keepsakes. Often times, they're priceless -- something you wouldn't give up, no matter what price you were offered.

And while stocks rarely have a deep sentimental value, that doesn't mean there are some worth holding -- perhaps forever.

So, here's why I plan on holding Amazon (AMZN -1.51%) and Tesla (TSLA -0.56%) for good.

Jar full of hundred-dollar bills.

Image source: Getty Images.

1. Amazon

If I could only own one stock, it would be Amazon. The reason is simple: Because of its diverse business segments, when you own shares of Amazon, it's like owning more than one company. It's like having an ownership stake in a retailer, a digital media company, a cloud provider, an AI startup, and a logistics powerhouse, all rolled into one.

Even better, many of these segments are the best at what they do. For example, Amazon Web Services (AWS) controls roughly one-third of the vast cloud services market. Amazon is growing its digital ad segment, which generated more than $9.5 billion in its most recent quarter (the three months ending on March 31) and grew 33% year over year. That's to say nothing of Amazon's sprawling e-commerce business, which has over 200 million Prime members.

What's more, market sentiment is coming around to the fact that Amazon's management has made tough decisions to cut costs that will result in higher profits. Estimates for this year's earnings per share are up from $1.41/share three months ago to $1.58/share today. I anticipate those earnings estimates will continue to rise as more analysts begin to price in the cost savings. 

However, I want to own shares of Amazon for the long term because of the company's massive reach and diverse businesses that should stand the test of time.

2. Tesla

Another stock I plan on holding for life is Tesla.

Let me be honest: I was wrong about Tesla. For many years, I thought the company would never produce enough electric vehicles (EVs) at the scale necessary to become a real player in the automotive marketplace. 

However, that's all changed. Now, Tesla is producing well over 1 million EVs annually, as new factories in Germany and Texas have come online. Moreover, the company is planning on building a new factory in Mexico.

At any rate, Tesla has more than proven that EVs are the future of the automotive industry. And this means Tesla stands to lead the way as the world makes the transition from internal combustion vehicles to EVs. Indeed, the International Energy Agency predicts that by 2030, there will be about 350 million EVs worldwide, as opposed to the 16.5 million at the end of 2021.

But the reasons I have for owning Tesla go beyond the fact that the company is the clear winner in a world that will rely on EVs for transport. Tesla not only wants to make vehicles that get you around, but it also wants to change the very nature of an automobile.

Tesla's full self-driving (FSD) software aims to completely alter the driving experience by removing the need for human intervention. And while critics can point out that FSD still hasn't arrived, it continues to get closer to a reality. Like Hemingway's adage that someone tends to go bankrupt "slowly, then all at once," I think FSD will follow the same path. Once naysayers see the writing on the wall and realize that Tesla's FSD will eventually come to pass, it will be hard to overlook the massive value in owning a Tesla -- and its stock.

The prospect of robotaxis -- which make up a big reason why Cathie Wood has a $2,000 price target on Tesla shares -- would alter the entire cost structure of owning a vehicle. After all, if a car could generate cash flow while the owner isn't using it, how much would a consumer be willing to pay for it?

In summary, Tesla is a company with one eye squarely on the future. It continues to innovate, despite its early lead in the race to supply the world with the EVs that will make the internal combustion engine a relic. And that's why I want to own its shares forever.