That is actually a common mistake. I suggest that you go, in the IDE, to File, Preferences and set compiler warnings to all. That line of code will generate a warning. Warnings will allow the code to compile, but not necessarily work right. You should always fix warnings, but you can't if you don't know about them.
What is sending data and to where? The serial transmit buffer is 64 bytes so as long as you send data fast enough to not fill that buffer serial output will not be effected.
I can't really say about best practice, I am far from a pro. For me the best practice is one that works and that I understand. Nothing wrong with any of those strategies. I have used most at different times.
For some data it makes sense to send periodically. Like regularly sampled ADC data. Send a data set each sample period.
Other times only when the data changes. Like data for an LCD.
The serial input basics tutorial may have information of interest.