Hmmm so that's why early check in is getting quite difficult and problematic at some hotels.
If nobody informs the hotel that they are checking out, housekeeping won't be inforned to prepare the room for the next guest.
A cascade stack of phantom occupied rooms which delay the turnover in time .....

By playing devil's advocate,
this ofcourse would never impair a hotel with many standard rooms and 24/7 housekeeping,
but when there a limited suites that keep being phantom occupied, i do feel it is a bit of an inconsideration.

Returning back on topic:
- if booking the room a day before as to accomodate a very early arrival, you'll get the 1 EQN
Experience:
IC David TLV, IC SIN : however remember to inform the hotel about your plan as guests who do not appear at 23.59 might be listed as noshows.

- if booking the room an extra day as to accommodate a very late departure (as in 01.30 AM midnight morning the next day) , you'll get the 1 EQN
Experience :
IC David TLV,
+ hotels in Egypt & India : however remember to inform the hotel about your plan as courtesy so they can prepare the vacated room for the next guest

PS: looking with an Ocean 8 lens from timestamp 01:04 ...
If Sandra Bullock can insinuate herself in a free stay due to guests officially checking out,
what rampage can be caused if someone is vacating their room without officially informing reception
If i would have a devious and cunning plan like Baldrick, ........
I dare say, it could promptly give someone blessed with a devious mind, an enormous opportunity for mischief if a room is still phantom occupied in someone else's name.... Enough feed for those harbouring a grudge or embody the epitome of hatred & deceit.

As please don't forget that any personal local legal stay obligations with the hotel only end officially when you finish the procedures and checkout. .........