Darts can vary in quality based on the materials used to make them. There are several types of materials that are used to create darts, namely brass, nickel or silver, and tungsten.
Darts made out of brass is the cheapest type of darts due to it being made out of dense metal, which makes it quite easy to use. However, brass darts are considered so soft that the grip often wears down faster. Furthermore, the consistency of the brass darts are not consistent and tend to vary due to it being mass produced. Brass darts are popularly used in taverns and bars as it is inexpensive.
For nickel darts, they are also quite a dense metal just like brass and is also not very expensive. Nickel darts are also mass produced but unlike brass darts, nickel is far more durable and harder in material which prevents the grip from getting worn out quickly. Also, nickel darts are similar to brass that makes it an excellent choice for beginners to try while on a budget.
Finally, tungsten darts are much heavier and incredibly dense, which makes it extremely durable. Darts made out of denser metals tend to have a higher resistant to the keeping the grip from wearing out. Softer darts like nickel and brass have their grips disappear quickly due to friction, skin acid, or simply collision with other darts. Originally, tungsten darts only had around 40 to 50% of tungsten metal made into the dart barrel, but these days, modern darts are made 80 to 95% of it.
Interested in finding more information on darts and accessories. Have a peek here at https://www.darts.com/types-of-darts to read more about the right metal darts or plastic darts with plastic tips that are suitable for you and your skill level.