Imperfect tense query

Imperfect tense query
 

Why does this sentence contain the imperfect tense? - El teatro tenía tres salidas. Why can't I say, El teatro tuvo tres salidas?


Many Thanks
Lawrence

The preterite ALWAYS shows the beginning or ending of something.

"El teatro tuvo tres salidas" means either:

1. The theater acquired/gained/changed to have 3 exits. (Before the time of reference the theater did not have 3 exits, and at the time of reference the theater changed so that it would have 3 exits).

2. The theater lost/changed so that it no longer had 3 exits. (Before the time of reference the theater had 3 exits, and at the time of reference the theater changed so that the number of exits was not 3.)

On the other hand, the imperfect NEVER shows the beginning or ending of something, merely its continuation.

"El teatro tenía tres salidas" means:

The theater had 3 exits. (At the time of reference there were 3 exits; we say nothing about how many exists existed before the time of reference or after the time of reference.)

Thank you very much!