From the picture posted, the following may be the reasons,
1)The flood level of that region may be higher than normal building level at times of season.
2)The basement level to be filled upto the level of brickwork, so to draw seepaged water, pipes can be installed.
3)Other aesthetic reasons. The Engineer may think of some design that can be achieved with the first step of piping.
These are known as sweep holes
Whenever one side filled with soil I rainy season water may accumulated in that site which increases the soil pressure and lead the compound wall collapse.to avoid this these deep holes are provided so that the water can flow through the weep holes so that unnecessary soil pressure decreases.hope this explanation clarify your doubt.