Does the echo command create a swap file when it writes a line to a file?

I am currently working on a personal project, and I would like to simply record logs in the following way using the echo command. My question is if the echo command accesses the same file at the same time, will the swap file be created? Or is there a queue inside the echo command to make things work in order? example:

$ cat a.txt

aa
bb
cc

$ echo "apple" >> a.txt

aa
bb
cc
apple