It doesn’t meant that truth is always the simplest explanation, it means that given a set of possible explanations, the simplest one is the most likely.
For example, if a red ball rolls into my living room I can hypothesize how it go there:
1) Someone rolled the ball into the room.
2) The ball is a reflection from a parallel plane.
3) The ball is a trick of my imagination.
4) The ball is stationary; in reality I rolled into the ball’s room and only perceived the ball as rolling into my room.
While any or all of these could be true, statistically speaking (Bayesian statistics), the simplest explanation is the most likely. Simple in this context means requiring the fewest number of forces, coordinates, or inertial frames of reference (since this is a physics problem) to explain the action.
Therefore, Occam’s Razor is a guiding principle for conducting scientific inquiry. It says to spend time analyzing the simplest hypotheses first before moving on to more difficult scenarios. Occam’s Razor is NOT intended to prove that something IS true because it is simpler. It only states that it is MORE likely.
The principle of Occam’s Razor is actually ubiquitous in nature. Entropy, conservation of energy and momentum, and the path of light through a series of optics are all examples of the most direct path being chosen. In quantum mechanics however, it’s necessary to sum over all possible paths to obtain a correct answer (even highly improbable paths). This would seem to violate the Principle of Least Action, however, after summing over improbably paths they tend to “cancel out” and the most likely paths are the simplest ones.