assigning variable value using echo

Shell Programming and Scripting
1

I am modifying an existing script and it has the following line:
export SomeEnvVar=`echo ${SomeLocalVar}`

Why wouldn't it just read:
export SomeEnvVar=${SomeLocalVar}

Is there some reason to use echo instead of a direct assignment? :confused:

2 
#!/bin/ksh

a='1
2
3
4'

b=`echo ${a}`
c="${a}"

echo "b->[$b]"
echo "c->[$c]"
3

Thanks - I understand now. :o