Temporary ordination is common in Burma. Temporary monks are known as Dullabha = difficult to get. That is because (rare), to meet the Buddha sāsana is rare, and to ordain as a bhikkhu in that sāsana is rare.
The custom in Burma is for many men (and some women) to enter the Sangha at some stage in their life at least once, and some do it many times. During early adolescence they may become a novice, and at 19 years from conception they enter the Sangha again as a bhikkhu.
It is not uncommon for them to stay for only two weeks — often during the Burmese New Year vacation when many offices and colleges are closed. Young novices may stay only a matter of days.
If the abbot is good, they will get some useful education and training. If they are well-educated Buddhists from pious families they will already have a basic understanding of what the monks' life entails, and what the benefits of meditation are.
On balance, I think it is a beneficial custom, but it is unfortunate if young men are bribed and cojouled into become monks by relatives, although they have neither the will mor wisdom to do it voluntarily.
If you have the opportunity to ordain, and wish to meditate seriously, do take it — you will learn a lot more from living the monk's life than looking at how well or badly others manage to do it.
• • • • (Upasampadā: 24th June, 1979)