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The SQL query with joins can take a lot of time due to several reasons:

1. Complex query: If the query involves many tables and conditions, it can take a lot of time as the database needs to execute all the joins, filters, and aggregations.

2. Indexing: If the tables being joined are large and not indexed correctly, it can take a lot of time to fetch the required data.

3. Hardware limitations: If the server hardware does not have enough resources like CPU, RAM, or Hard Disk space, it can impact the query performance.

4. Network latencies: If the database server and application server are present on different networks, it can lead to network latencies, resulting in slower query processing.

5. Deadlocks: Sometimes, multiple queries trying to access the same table can cause deadlocks, causing the query to wait for other processes to complete.

6. Query design: Poorly designed queries can also take a lot of time as the database engine may need to perform unnecessary operations or scan a large number of rows.

To optimize the query performance, one can analyze and optimize table structures, use appropriate indexing, and rewrite the query to improve its efficiency.