It has been observed that developers generally put every other external content in head section whereas it can be comparatively slower if not put in appropriate section
Stylesheets should be referenced as
<link rel=’stylesheet’ href=’bootstrap.min.css’ type=’text/css’ />
<!– Body content –>
Why : Since everything gets downloaded synchronously on webpage, so whatever comes first would be downloaded first. If the scripts files are heavy then the page content would not be available until the external content is loaded.
Expectation : The website content should be made available to the user as soon as possible. Since the user might not be interested in performing any action
Result : Website This can only be observed on slow network connection between server and the client browser since intranet sites generally do not observe network latency for the usual page size including script which can be typically upto 1-2 MB(s).