The words “I can’t” are a lie you tell yourself and others. It’s a form of giving up, of conceding defeat before you have even tried. “I can’t” is a form of surrendering before you have even begun. It’s also a way to absolve yourself of responsibility.
Maybe “you can’t,” like all the people who lacked the skill set or competence to do whatever it is you need to do—until they tried. It could be that you don’t know where to start, the same place everyone finds themselves before they began. Like all of us, you were born not knowing how to do all the incredible things you now do without so much as a thought.
It’s practically a miracle that you know how to speak, even though you know almost nothing about grammar and syntax. It would be exceedingly unlikely that you could diagram a sentence, yet everyone understands you, and you understand them. You can drive a car, even one without an automatic transmission, without being conscious of what you are doing, making it to your destination with little conscious effort. At some point, you learned algebra, and even though you have mostly forgotten everything except solving for x, you knew enough to pass the class.
When you say, “I can’t get this person to return my call,” or “I can’t get a meeting,” you are describing the current state of an outcome you are pursuing, not your ability to produce the outcome.
When you use the words “I can’t,” adding the word “yet” to the end of the sentence transforms what you said from an untruth to a statement of fact, a fact that will only be true for the period of time between the words leaving your lips and the time you begin to take action.