I may be a fairly good sailor at this point in my life but there were times when, like Peter, I had to be humbled. One time I was sailing a Sunfish in Michigan. I had trouble controlling the wind which was building and the sailboat and I ended up in shallow water. I had to walk the boat back into deep water. About that time an officer spotted me and towed me back to deep water. I was humiliated as my friends watched me be blown off course. It was a most embarrassing moment.
Peter was not called because he had any special qualifications except for the fact he made a choice to go where Jesus led him. He was also called in the midst of his daily living. It didn't take place in some holy place like the temple. For sure, his willingness to "follow" would change his life, reversing some of his normal priorities and changing the lives of others too.