I have no idea where this is comming from, but it is not a regular thing. It is the only user in itwiki with a negative editcount. And in e.g. enwiki there is not a single user with a negative edit count. Also the account is quite old. So this is some random data corruption?

MariaDB [itwiki_p]> select user_id, user_name, user_editcount from user where user_editcount < 0;
+---------+-----------------------+----------------+
| user_id | user_name             | user_editcount |
+---------+-----------------------+----------------+
|  110871 | Tetesco sotto il sale |           -999 |
+---------+-----------------------+----------------+
1 row in set (0.64 sec)

MariaDB [itwiki_p]>

MariaDB [enwiki_p]> select user_id, user_name, user_editcount from user where user_editcount < 0;
Empty set (42.14 sec)

MariaDB [enwiki_p]>

In T305329#7827213, @Reedy wrote:

MariaDB [itwiki]> select * from actor where actor_user = 110871;
+----------+------------+-----------------------+
| actor_id | actor_user | actor_name            |
+----------+------------+-----------------------+
|   272621 |     110871 | Tetesco sotto il sale |
+----------+------------+-----------------------+
1 row in set (0.001 sec)

MariaDB [itwiki]> select count(*) from revision where rev_actor = 272621;
+----------+
| count(*) |
+----------+
|       88 |
+----------+
1 row in set (0.002 sec)

And the fix:

MariaDB [itwiki]> UPDATE user SET user_editcount=88 where user_id = 110871;
Query OK, 1 row affected (0.003 sec)
Rows matched: 1  Changed: 1  Warnings: 0

What about deleted edits? I was going to suggest setting to null so that UserEditTracker::initializeUserEditCount() would populate it according to existing logic

They’re indef blocked as a sock puppet. Does anyone really care?

That and UserEditTracker::initializeUserEditCount() only does revision anyway...

In T305329#7827296, @Reedy wrote:

That and UserEditTracker::initializeUserEditCount() only does revision anyway...

Oh, I misread it. Nevermind then, doesn't matter