I often see people mark a reply as the Solution when it does not contain the Solution to the question.
A reply like “Oh, yes! What you said fixes my problem!” is not a solution. It is an acknowledgment of a solution, which happened in an earlier reply.
The Solution should be the answer to the problem posed in the topic, not the reply indicating the the problem has been solved for the topic author.
Example
@jabid asked how to make a Whatsapp link to dial a number.
This was marked as the solution, but it is not a solution:
This does not contain any information about making a Whatsapp link.
Here is the solution by @Jeff_Hager :
This is the solution because it actually tells you how to make a Whatsapp link.