Most companies wanting to import security in this way, i.e. to receive a Bank Guarantee or SBLC under Collateral Transfer Agreements, want to either (a) raise money by credit or loan, or (b) enter into a trade position. There are other reasons but the former two represent around 90%+ of all applications.
Companies choose to seek these facilities as they do not have the collateral of their own to secure borrowings. Others may wish to leverage investment and trade positions. Companies can obtain up to 900% leverage over 12 months using these types of facilities.
Companies seeking short to medium term loans can also use such facilities to attract investment, credit and loans.