riddle - What 5-letter word am I?

Some use me unaware.

Some call me lazy.
The most-used did a 180,
And then you saw me.

I'm short and neutral.
By the time you've read these 8 lines,
You'll have used me at least 8 times,
And maybe even up to 18 times.

What 5-letter word am I?

Post a detailed explanation with your answer, please.

Answer

You are

schwa

Some use me unaware.

Some people have never heard of the schwa.

Some call me lazy.

In English, the schwa occurs in many unstressed syllables. Since it is unstressed, some people call it lazy.

The most-used did a 180, And then you saw me.

e is the most common letter in the English language. Rotate it 180 degrees and you get ə, which represents the schwa.

I'm short and neutral.

The schwa is a short neutral vowel sound.

By the time you've read this, You'll have used me at least 8 times, And maybe even up to 18 times.

Using the Google define feature to get the IPA pronunciations of the words in the first 8 lines, I came up with the following words that can be pronounced with a schwa:

Some: səm
unaware: ˌənəˈwer
Some: səm
The: T͟Hē, T͟Hə
a: ā, ə
one (in 180): wən

And: and, (ə)n
and: and, (ə)n
neutral: ˈn(y)o͞otrəl
the: T͟Hē, T͟Hə
you've: yo͞ov, yəv
have: hav, həv, (ə)v
at: at, ət
And: and, (ə)n
even: ˈēvən
up: əp

to: to͞o, tə

Since some words have multiple pronunciations, some of which may not use the schwa, that comes out to a minimum of 8 schwas and a maximum of 18 schwas.