Why do some people wear the Mala around their neck?

In simple language Mala is garland. Various types of beads or flowers or any other materials are threaded together in it. It is a type of ornament which has been used since ancient time.
What is an ornament?
Ornaments play a vital role in the human life for beautification. The Sanskrit word for ornament, is AlaMkar. The etymology of the word can be given as AlaM kraoit [it AlaMkar: that is ‘the ornament is the one which gives full stop to the beautification or by the use of which the process of ornamenting body ends’. Hence, in the step of beautification ornaments are used at the end to give a final touch.
Traditionally, there are various types of ornaments. Various types of garlands, anklets, figure rings, ear ornaments, etc. were used since ancient period.
The real reason of Ornamentation
Though the main purpose of ornament is given as beautification, the actual purpose can be given beyond it. ‘Ornaments work as the protection’ is hidden reason of wearing ornaments. This protection can be of either the mercy of deities or from the protection against evil. Various ornaments and gems are mainly used as the protection from the evil.
In Charaka Samhita it is said that ‘good, healthy, graceful and beautiful body is the abode of the gods. On the other hand diseased, unhealthy body is abode of evil. Hence, to make the body healthy and beautiful the use of gems and ornaments is suggested by the Charaka.
Many of the ornaments are of metal. And metal works as the amulet for removal of evil. Similarly, various gems are also suggested for the removal of evil.
Hence, beautification and protection, these are two reasons for the use of ornaments. But beautification is the next step of protection.

Mala as an important ornament
As said mala is the garland of various beads, gems, metal chain or other useful material. It is one of the most popular and important ornament. These malas adorn the neck. It is prominently visible from the front because it is worn on the neck. Hence, from the front it is very easily visible.

Reason
As an important ornament, the mala is frequently used for the various purposes. Beautification is the mainly purpose for wearing the mala.
It is such a type of ornaments in which so many gems and stones can be used together. Hence it is the best type of ornament to wear like it is suggested in the Ayurveda to make the body healthy.
Another important reason of wearing mala is to expel evil from and around the body. From the front it is easily noteworthy, hence it protects from the evil eyes.
One need not to be spiritual if he/ she wears beads around the neck. It is also considered that this ornament is used for meditation as well. The religion has nothing to do with it if talking practically. Many stones and beads made up in a garland are scientifically effective and hence gives up the different energies and for different uses. All possible natural materials are used to create a particular type of mala, hence gives the impact of connectivity.

The concept of wearing beads from ancient times till now has a different meaning at all. People used to wear them just for a spiritual guidance, but now the use is more practical and one can weave their own faiths and beliefs in it.