We could say that chess players are born, but they are made. It could be quantified as if they were born with 10% chess talent, and the remaining 90% is all their work.
Talentmakes absolutely no sense without hard work. Talent alone can't get you far.
It depends almost entirely on the type of training you do and how many hours a day you do it. There's no really good way to measure talent. Usually people just look at someone with a high level of skill and assume that they were born talented. Some people are born with greater potential, but without hard work and without practicing their talent they will be of no use.
Music is a good example, with some evidence of genetic differences. For example, a study of 500 twins found that 80 percent of tonal deafness is inherited. Another found genes associated with the release of serotonin, which were related to musical creativity. You improve at chess faster than the people around you. Having a natural talent in a given field means that you understand things more easily than most people.
It's similar to studying at school or university. Some of us have to read the same page several times to understand what it's about, while others take a look and can work out the details on their own. In any chess club where children train in groups, there will be students who make impressive progress and others who fall far behind. Becoming a professional chess player requires the right combination of talent, hard work and environment. However, if you enroll in the Kasparov-Botvinnik chess school and face players like Vladimir Kramnik or Alexei Shirov, it's easy to get demotivated and decide that your chess talent is regular.
Genes are going to be a factor, but there are many more possible GMs (as far as genes are concerned) who don't play chess (or play it casually) than those who tried very hard and didn't succeed. It's one thing to be able to outshine children in a typical suburban chess club, where most competitors won't beat 1600 FIDE before quitting smoking. On the contrary, if his eyes shine with fury and he says he will fight back and recover his score, it is a sign that he may have a future as a chess player. Some children become unmotivated to study chess just because they don't like the coach, the format, or other members of the class. Adriaan de Groot, a famous psychologist and chess teacher, demonstrated that master-level players were able to recognize the patterns of the pieces on the chessboard much faster than non-teachers. Chess is an inclusive game that is quite popular among special people, but it is still demanding if you plan to dedicate yourself to this activity professionally.
Quite a few wonders hit the roof and are exhausted at an early age, especially if their chess studies are mainly imposed by their parents. I think that the best chess players, on average, including many great teachers, definitely learn for this reason. Chess skills can certainly be developed without any particular talent, but personally I believe that, all things being equal, people with a natural talent for something can reach a higher level than those who don't. Fabiano Caruana takes physical training very seriously and is known as a great calculator who can withstand chess marathons without losing focus. In addition, they have the advantage that you don't even have to master chess to “diagnose yourself or your children” using this short list. Like many other parents, the lady wanted to know if her daughter had enough chess talent to keep going.