Life Insurance for tax deductible

Please can anyone share your experience on this.

All of my Thai colleagues advised me to buy life insurance for tax deductible.

I came down to the bank and this is what they offered:

I put in 100k every year in 5 years, I can take the money out after 10 years. Based on current tax rate, I will not have to pay 30% tax on this amount. They will then pay the interest of 5000 per year.

Return after 10 years: 475,800 + 50,000 (5,000 per year in 10 years) + 30% tax (30k x 5) = 675,800 baht

So I make a return of 175,800/10 years so 17,580 per year - approximately 3.5% of my investment (500.000).

3.5% is not that impressive. So why people are so excited about this? Can anybody please shed some light?