The rosary is a prayer rule. All chaplets are prayer rules and the rosary is the most popular.
We are to “pray without ceasing”.
The Liturgy of the Hours is one way of fulfilling this command. Christians from the earliest days all prayed at different times of the day, sanctifying time. In the apostolic era time was kept in discreet three hour segments called a “watch”, and Christians developed the practice of pausing at the turn of the watch to pray the Psalms.
Cenobites (monks) and hermits have kept this practice into modern times, changing it as needed over the years. Most monks and nuns of early days were not literate but had the benefit of memorizing the Psalms through repitition.
The local people, mostly poorly educated, wanted to also have a devotion that would serve the purpose of a prayerful and meditative experience. The rosary then, came to be that devotion.
To quote another website:
**The rosary did not originate in a miraculous way, given in a form never to be changed. Throughout the early middle ages, various ways were developed for participating in some way in the Church’s continual prayer of the 150 psalms in the Divine Office. At first, individuals said the Our Father 150 times; later, as the Hail Mary became more widespread, this prayer was repeated 150 times. **
**Our present form of the rosary developed in Carthusian monasteries in the 14th and 15th centuries. It consisted of the Scriptural verses of the Hail Mary with 50, then 150, little “inserts” (clausulae) added after the name of Jesus. The clausulae became the “mysteries” and were divided into three sets of fifty each. Finally, the clausulae or mysteries were reduced to the present fifteen joyful, sorrowful, and glorious mysteries. **
**In the middle ages, there were different forms for the second part of the Hail Mary. The present text appeared for the first time in the Roman Breviary (1568). No directive indicated that this form was to be used in the Rosary. In its original approbation (1569), the rosary was spoken of as the “contemplation of the mysteries of Christ combined with the Angel’s Greeting.” **The granting of indulgences caused the rosary’s form to remain unchanged for more than four hundred years. All indulgenced prayers were to be recited according to the prescribed form–without any deviation. Even commendable customs, such as the insertion of the clausulae, were suppressed unless an exception was granted, as was done for German-speaking areas where the clausulae were customarily added.
In light of the origins of the rosary as a substitute for the 150 Psalms, and it’s original form consisting of Paternosters, I am very flexible as to the prayer devotions I might recommend.
Usually if I find an interested inquirer who is put off by the rosary I suggest they try it as 150 Our Fathers or 150 Jesus Prayers. They can break it into decades with a doxology, or a creed, eventually trying the Hail Mary once between each decade.
There is no reason for this form of prayer to be a difficulty, especially considering the Mysteries that are such valuable meditiations for a new Christian.