Mysql. JOIN to small table blocks using indexes on the main one - mysql

Question

MySQL version 5.7.17
When I use JOIN for small tables, MySQL don't allow me to use index on the main table.
Compare:
EXPLAIN SELECT `ko_base_client_orders`.*
FROM `ko_base_client_orders`
LEFT JOIN `ko_base_new_perspe` AS `ko_of`
ON (`ko_of`.`id` = `ko_base_client_orders`.`office`)
ORDER BY `order_time` DESC
LIMIT 10 OFFSET 0;
+----+-------------+-----------------------+------------+-------+---------------+---------+---------+------+-------+----------+-----------------------------------------------------------------+
| id | select_type | table | partitions | type | possible_keys | key | key_len | ref | rows | filtered | Extra |
+----+-------------+-----------------------+------------+-------+---------------+---------+---------+------+-------+----------+-----------------------------------------------------------------+
| 1 | SIMPLE | ko_base_client_orders | NULL | ALL | NULL | NULL | NULL | NULL | 60737 | 100.00 | Using temporary; Using filesort |
| 1 | SIMPLE | ko_of | NULL | index | PRIMARY | PRIMARY | 4 | NULL | 2 | 100.00 | Using where; Using index; Using join buffer (Block Nested Loop) |
+----+-------------+-----------------------+------------+-------+---------------+---------+---------+------+-------+----------+-----------------------------------------------------------------+
2 rows in set, 1 warning (0.00 sec)
and the same query with index hint:
EXPLAIN SELECT `ko_base_client_orders`.*
FROM `ko_base_client_orders`
LEFT JOIN `ko_base_new_perspe` AS `ko_of`
FORCE INDEX FOR JOIN (`PRIMARY`)
ON (`ko_of`.`id` = `ko_base_client_orders`.`office`)
ORDER BY `order_time` DESC
LIMIT 10 OFFSET 0;
+----+-------------+-----------------------+------------+--------+---------------+------------+---------+---------------------------------+------+----------+-------------+
| id | select_type | table | partitions | type | possible_keys | key | key_len | ref | rows | filtered | Extra |
+----+-------------+-----------------------+------------+--------+---------------+------------+---------+---------------------------------+------+----------+-------------+
| 1 | SIMPLE | ko_base_client_orders | NULL | index | NULL | order_time | 6 | NULL | 10 | 100.00 | NULL |
| 1 | SIMPLE | ko_of | NULL | eq_ref | PRIMARY | PRIMARY | 4 | e3.ko_base_client_orders.office | 1 | 100.00 | Using index |
+----+-------------+-----------------------+------------+--------+---------------+------------+---------+---------------------------------+------+----------+-------------+
In second case MySQL uses key for order_time, but in first example it ignores index and scans the entire table.
I can not predict which table would be small, and which would not (it differs from project to project), so I don't want to use index hints all the time. Is there another solution for this problem?